A 2010 review by the Cochrane collaboration found that no medications show promise for "the core BPD symptoms of chronic feelings of emptiness, identity disturbance and abandonment". However, the authors found that some medications may impact isolated symptoms associated with BPD or the symptoms of comorbid conditions. A 2017 review examined evidence published since the 2010 Cochrane review and found that "evidence of effectiveness of medication for BPD remains very mixed and is still highly compromised by suboptimal study design".

Of the typical antipsychotics studied in relation to BPD, haloperidol may reduce anger and flupenthixol may reduce the likelihood of suicidal behavior. Among the atypical antipsychotics, one trial found that aripiprazole may reduce interpersonal problems and impulsivity. Olanzapine may decrease affective instability, anger, psychotic paranoid symptoms, and anxiety, but a placebo had a greater ameliorative impact on suicidal ideation than olanzapine did. The effect of ziprasidone was not significant.

Of the mood stabilizers studied, valproate semisodium may ameliorate depression, interpersonal problems, and anger. Lamotrigine may reduce impulsivity and anger; topiramate may ameliorate interpersonal problems, impulsivity, anxiety, anger, and general psychiatric pathology. The effect of carbamazepine was not significant. Of the antidepressants, amitriptyline may reduce depression, but mianserin, fluoxetine, fluvoxamine, and phenelzine sulfate showed no effect. Omega-3 fatty acid may ameliorate suicidality and improve depression. As of 2017, trials with these medications had not been replicated and the effect of long-term use had not been assessed.

Because of weak evidence and the potential for serious side effects from some of these medications, the UK National Institute for Health and Clinical Excellence (NICE) 2009 clinical guideline for the treatment and management of BPD recommends, "Drug treatment should not be used specifically for borderline personality disorder or for the individual symptoms or behavior associated with the disorder." However, "drug treatment may be considered in the overall treatment of comorbid conditions". They suggest a "review of the treatment of people with borderline personality disorder who do not have a diagnosed comorbid mental or physical illness and who are currently being prescribed drugs, with the aim of reducing and stopping unnecessary drug treatment".

Treatment for OCPD includes psychotherapy, cognitive behavioral therapy, behavior therapy or self-help. Medication may be prescribed. In behavior therapy, a person with OCPD discusses with a psychotherapist ways of changing compulsions into healthier, productive behaviors. Cognitive analytic therapy is an effective form of behavior therapy.

Treatment is complicated if the person does not accept that they have OCPD, or believes that their thoughts or behaviors are in some sense correct and therefore should not be changed. Medication alone is generally not indicated for this personality disorder. Selective serotonin reuptake inhibitors (SSRIs) may be useful in addition to psychotherapy by helping the person with OCPD be less bogged down by minor details, and to lessen how rigid they are.

People with OCPD are three times more likely to receive individual psychotherapy than people with major depressive disorder. There are higher rates of primary care utilization. There are no known properly controlled studies of treatment options for OCPD. More research is needed to explore better treatment options.

Long-term psychotherapy is currently the treatment of choice for BPD. While psychotherapy, in particular dialectical behavior therapy and psychodynamic approaches, is effective, the effects are small.

More rigorous treatments are not substantially better than less rigorous treatments. There are six such treatments available: dynamic deconstructive psychotherapy (DDP), mentalization-based treatment (MBT), transference-focused psychotherapy, dialectical behavior therapy (DBT), general psychiatric management, and schema-focused therapy. While DBT is the therapy that has been studied the most, all these treatments appear effective for treating BPD, except for schema-focused therapy. Long-term therapy of any kind, including schema-focused therapy, is better than no treatment, especially in reducing urges to self-injure.

Cognitive behavioral therapy (CBT) is also a type of psychotherapy used for treatment of BPD. This type of therapy relies on changing people's behaviors and beliefs by identifying problems from the disorder. CBT is known to reduce some anxiety and mood symptoms as well as reduce suicidal thoughts and self-harming behaviors.

Mentalization-based therapy and transference-focused psychotherapy are based on psychodynamic principles, and dialectical behavior therapy is based on cognitive-behavioral principles and mindfulness. General psychiatric management combines the core principles from each of these treatments, and it is considered easier to learn and less intensive. Randomized controlled trials have shown that DBT and MBT may be the most effective, and the two share many similarities. Researchers are interested in developing shorter versions of these therapies to increase accessibility, to relieve the financial burden on patients, and to relieve the resource burden on treatment providers.

From a psychodynamic perspective, a special problem of psychotherapy with people with BPD is intense projection. It requires the psychotherapist to be flexible in considering negative attributions by the patient rather than quickly interpreting the projection.

Some research indicates that mindfulness meditation may bring about favorable structural changes in the brain, including changes in brain structures that are associated with BPD. Mindfulness-based interventions also appear to bring about an improvement in symptoms characteristic of BPD, and some clients who underwent mindfulness-based treatment no longer met a minimum of five of the DSM-IV-TR diagnostic criteria for BPD.

A major option for many mental disorders is psychiatric medication and there are several main groups. Antidepressants are used for the treatment of clinical depression, as well as often for anxiety and a range of other disorders. Anxiolytics (including sedatives) are used for anxiety disorders and related problems such as insomnia. Mood stabilizers are used primarily in bipolar disorder. Antipsychotics are used for psychotic disorders, notably for positive symptoms in schizophrenia, and also increasingly for a range of other disorders. Stimulants are commonly used, notably for ADHD.

Despite the different conventional names of the drug groups, there may be considerable overlap in the disorders for which they are actually indicated, and there may also be off-label use of medications. There can be problems with adverse effects of medication and adherence to them, and there is also criticism of pharmaceutical marketing and professional conflicts of interest.

Treatment of avoidant personality disorder can employ various techniques, such as social skills training, cognitive therapy, and exposure treatment to gradually increase social contacts, group therapy for practicing social skills, and sometimes drug therapy.

A key issue in treatment is gaining and keeping the patient's trust, since people with avoidant personality disorder will often start to avoid treatment sessions if they distrust the therapist or fear rejection. The primary purpose of both individual therapy and social skills group training is for individuals with avoidant personality disorder to begin challenging their exaggerated negative beliefs about themselves.

Significant improvement in the symptoms of personality disorders is possible, with the help of treatment and individual effort.

STPD is rarely seen as the primary reason for treatment in a clinical setting, but it often occurs as a comorbid finding with other mental disorders. When patients with STPD are prescribed pharmaceuticals, they are most often prescribed the same drugs used to treat patients suffering from schizophrenia including traditional neuroleptics such as haloperidol and thiothixene. In order to decide which type of medication should be used, Paul Markovitz distinguishes two basic groups of schizotypal patients:

- Schizotypal patients who appear to be almost schizophrenic in their beliefs and behaviors (aberrant perceptions and cognitions) are usually treated with low doses of antipsychotic medications, e.g. thiothixene. However, it must be mentioned that long-term efficacy of neuroleptics is doubtful.

- For schizotypal patients who are more obsessive-compulsive in their beliefs and behaviors, SSRIs like Sertraline appear to be more effective.

Lamotrigine, an anti-convulsant, appears to be helpful in dealing with social isolation.

Electroconvulsive therapy (ECT) is sometimes used in severe cases when other interventions for severe intractable depression have failed. Psychosurgery is considered experimental but is advocated by some neurologists in certain rare cases.

Counseling (professional) and co-counseling (between peers) may be used. Psychoeducation programs may provide people with the information to understand and manage their problems. Creative therapies are sometimes used, including music therapy, art therapy or drama therapy. Lifestyle adjustments and supportive measures are often used, including peer support, self-help groups for mental health and supported housing or supported employment (including social firms). Some advocate dietary supplements.

Reasonable accommodations (adjustments and supports) might be put in place to help an individual cope and succeed in environments despite potential disability related to mental health problems. This could include an emotional support animal or specifically trained psychiatric service dog.

The most effective treatment for an individual with conduct disorder is one that seeks to integrate individual, school, and family settings. Additionally, treatment should also seek to address familial conflict such as marital discord or maternal depression.

Despite recent initiatives to study psychopathology along dimensions of behavior and neurobiological indices, which would help refine a clearer picture of the development and treatment of externalizing disorders, the majority of research has examined specific mental disorders. Thus, best practices for many externalizing disorders are disorder-specific. For example, substance use disorders themselves are very heterogeneous and their best-evidenced treatment typically includes cognitive behavioral therapy, motivational interviewing, and a substance disorder-specific detoxification or psychotropic medication treatment component. The best-evidenced treatment for childhood conduct and externalizing problems more broadly, including youth with ADHD, ODD, and CD, is parent management training, a form of cognitive behavioral therapy. Additionally, individuals with ADHD, both youth and adults, are frequently treated with stimulant medications (or alternative psychotropic medications), especially if psychotherapy alone has not been effective in managing symptoms and impairment. Psychotherapy and medication interventions for individuals with severe, adult forms of antisocial behavior, such as antisocial personality disorder, have been mostly ineffective. An individual's comorbid psychopathology may also influences the course of treatment for an individual.

No medications are indicated for directly treating schizoid personality disorder, but certain medications may reduce the symptoms of SPD as well as treat co-occurring mental disorders. The symptoms of SPD mirror the negative symptoms of schizophrenia, such as anhedonia, blunted affect and low energy, and SPD is thought to be part of the "schizophrenic spectrum" of disorders, which also includes the schizotypal and paranoid personality disorders, and may benefit from the medications indicated for schizophrenia. Originally, low doses of atypical antipsychotics like risperidone or olanzapine were used to alleviate social deficits and blunted affect. However, a recent review concluded that atypical antipsychotics were ineffective for treating personality disorders. In contrast, the substituted amphetamine Bupropion may be used to treat anhedonia. Likewise, Modafinil may be effective in treating some of the negative symptoms of schizophrenia, which are reflected in the symptomatology of SPD and therefore may help as well. Lamotrigine, SSRIs, TCAs, MAOIs and Hydroxyzine may help counter social anxiety in people with SPD if present, though social anxiety may not be a main concern for the people who have SPD. However, it is not general practice to treat SPD with medications, other than for the short term treatment of acute co-occurring Axis I conditions (e.g. depression).

There are many different forms (modalities) of treatment used for personality disorders:

- Individual psychotherapy has been a mainstay of treatment. There are long-term and short-term (brief) forms.

- Family therapy, including couples therapy.

- Group therapy for personality dysfunction is probably the second most used.

- Psychological-education may be used as an addition.

- Self-help groups may provide resources for personality disorders.

- Psychiatric medications for treating symptoms of personality dysfunction or co-occurring conditions.

- Milieu therapy, a kind of group-based residential approach, has a history of use in treating personality disorders, including therapeutic communities.

- The practice of mindfulness that includes developing the ability to be nonjudgmentally aware of unpleasant emotions appears to be a promising clinical tool for managing different types of personality disorders.

There are different specific theories or schools of therapy within many of these modalities. They may, for example, emphasize psychodynamic techniques, or cognitive or behavioral techniques. In clinical practice, many therapists use an 'eclectic' approach, taking elements of different schools as and when they seem to fit to an individual client. There is also often a focus on common themes that seem to be beneficial regardless of techniques, including attributes of the therapist (e.g. trustworthiness, competence, caring), processes afforded to the client (e.g. ability to express and confide difficulties and emotions), and the match between the two (e.g. aiming for mutual respect, trust and boundaries).

According to Theodore Millon, the schizotypal is one of the easiest personality disorders to identify but one of the most difficult to treat with psychotherapy. Persons with STPD usually consider themselves to be simply eccentric, productive, or nonconformist. As a rule, they underestimate maladaptiveness of their social isolation and perceptual distortions. It is not so easy to gain rapport with people who suffer from STPD due to the fact that increasing familiarity and intimacy usually increase their level of anxiety and discomfort. In most cases they do not respond to informality and humor.

Group therapy is recommended for persons with STPD only if the group is well structured and supportive. Otherwise, it could lead to loose and tangential ideation. Support is especially important for schizotypal patients with predominant paranoid symptoms, because they will have a lot of difficulties even in highly structured groups.

People with schizoid personality disorder rarely seek treatment for their condition. This is an issue found in many personality disorders, which prevents many people who are afflicted with these conditions from coming forward for treatment: They tend to view their condition as not conflicting with their self-image and their abnormal perceptions and behaviors as rational and appropriate. There is little data on the effectiveness of various treatments on this personality disorder because it is seldom seen in clinical settings. However, those in treatment have the option of medication and therapy.

Another example of treatment besides coding is Functional Ideographic Assessment Template. The functional ideographic assessment template, also known as FIAT, was used as a way to generalize the clinical processes of functional analytic psychotherapy. The template was made by a combined effort of therapists and can be used to represent the behaviors that are a focus for this treatment. Using the FIAT therapists can create a common language to get stable and accurate communication results through functional analytic psychotherapy at the ease of the client; as well as the therapist.

Another way to treat histrionic personality disorder after identification is through functional analytic psychotherapy. The job of a Functional Analytic Psychotherapist is to identify the interpersonal problems with the patient as they happen in session or out of session. Initial goals of functional analytic psychotherapy are set by the therapist and include behaviors that fit the client's needs for improvement. Functional analytic psychotherapy differs from the traditional psychotherapy due to the fact that the therapist directly addresses the patterns of behavior as they occur in-session.

The in-session behaviors of the patient or client are considered to be examples of their patterns of poor interpersonal communication and to adjust their neurotic defenses. To do this, the therapist must act on the client's behavior as it happens in real time and give feedback on how the client's behavior is affecting their relationship during therapy. The therapist also helps the client with histrionic personality disorder by denoting behaviors that happen outside of treatment; these behaviors are termed "Outside Problems" and "Outside Improvements". This allows the therapist to assist in problems and improvements outside of session and to verbally support the client and condition optimal patterns of behavior". This then can reflect on how they are advancing in-session and outside of session by generalizing their behaviors over time for changes or improvement".

ASPD is considered to be among the most difficult personality disorders to treat. Because of their very low or absent capacity for remorse, individuals with ASPD often lack sufficient motivation and fail to see the costs associated with antisocial acts. They may only simulate remorse rather than truly commit to change: they can be seductively charming and dishonest, and may manipulate staff and fellow patients during treatment. Studies have shown that outpatient therapy is not likely to be successful, but the extent to which persons with ASPD are entirely unresponsive to treatment may have been exaggerated.

Those with ASPD may stay in treatment only as required by an external source, such as parole conditions. Residential programs that provide a carefully controlled environment of structure and supervision along with peer confrontation have been recommended. There has been some research on the treatment of ASPD that indicated positive results for therapeutic interventions.

Psychotherapy also known as talk therapy is found to help treat patients with ASPD.Schema therapy is also being investigated as a treatment for ASPD. A review by Charles M. Borduin features the strong influence of Multisystemic therapy (MST) that could potentially improve this imperative issue. However, this treatment requires complete cooperation and participation of all family members. Some studies have found that the presence of ASPD does not significantly interfere with treatment for other disorders, such as substance abuse, although others have reported contradictory findings.

Therapists working with individuals with ASPD may have considerable negative feelings toward patients with extensive histories of aggressive, exploitative, and abusive behaviors. Rather than attempt to develop a sense of conscience in these individuals, which is extremely difficult considering the nature of the disorder, therapeutic techniques are focused on rational and utilitarian arguments against repeating past mistakes. These approaches would focus on the tangible, material value of prosocial behavior and abstaining from antisocial behavior. However, the impulsive and aggressive nature of those with this disorder may limit the effectiveness of even this form of therapy.

The use of medications in treating antisocial personality disorder is still poorly explored, and no medications have been approved by the FDA to specifically treat ASPD. A 2010 Cochrane review of studies that explored the use of pharmaceuticals in ASPD patients, of which 8 studies met the selection criteria for review, concluded that the current body of evidence was inconclusive for recommendations concerning the use of pharmaceuticals in treating the various issues of ASPD. Nonetheless psychiatric medications such as antipsychotics, antidepressants, and mood stabilizers can be used to control symptoms such as aggression and impulsivity, as well as treat disorders that may co-occur with ASPD for which medications are indicated.

As it has already been mentioned, patients with organic personality disorder show a wide variety of sudden behavioural changes and dysfunctions. There are not a lot of information about the treatment of this mental health disorder. The pharmacological approach is the most common therapy among patients with organic personality disorder. However, the choice of drug therapy relies on the seriousness of patient's situation and what symptoms are shown. The choice and administration of specific drugs contribute to the reduction of symptoms of organic personality disorder. For this reason, it is crucial for patients' treatment to be assessed by clinical psychologists and psychiatrists before the administration of drug.

Additionally, the dysfunctions in expression of behaviour of patients with organic personality disorder and the development of symptom of irritability, which are caused by aggressive and self-injurious behaviours, can be dealt with the administration of carbamazepine. Moreover, the symptoms of this disorder can be decreased by the administration of valproic acid. Also, emotional irritability and signs of depression can be dealt with the use of nortriptyline and low-dose thioridazine. Except from the symptom of irritability, patients express aggressive behaviours. At the onset of drug therapy for effective treatment of anger and aggression, the drug of carbamazepine, phenobarbital, benztropine and haloperidol can be administrated in order to reduce the symptoms of patients with organic personality disorder. In addition, the use of propranolol may decrease the frequent behaviours of rage attacks.

Finally, it is important for patients to take part in psychotherapy sessions during the period of drug therapy. In this way, there is prevention and patients can be protected by negative effects of drugs on their organism and their behaviour. Furthermore, the clinicians can provide useful and helpful support to patients during these psychotherapy sessions. Thus, the combination of drug therapy with psychotherapy can lead to the reduction of symptoms of this disorder and the improvement of patients' situation.

When treating addictive personalities, the primary or presenting addiction needs to be treated first. Only once the behavior is under control can the person truly begin to do any of the therapeutic work necessary for recovery.

Common forms of treatment for addictive personalities include cognitive behavioral therapy, as well as other behavioral approaches. These treatments help patients by providing healthy coping skills training, relapse prevention, behavior interventions, family and group therapy, facilitated self-change approaches, and aversion therapy. Behavioral approaches include using positive reinforcement and behavioral modeling. Along with these, other options that help with treating those who suffer with addictive personality include social support, help with goal direction, rewards, enhancing self-efficacy and help teaching coping skills.

Another important skill to learn in treatment, which can be overlooked, is self-soothing. People with addictive personalities use their addictions as coping mechanisms when in stressful situations. However, since their addictions do not actually soothe them, so much as they provide momentary relief from anxiety or uncomfortable emotions, these individuals feel the need to use their addiction more often. Thus, self-soothing and other mindfulness-based interventions can be used for treatment because they provide healthier coping mechanisms once the addictive behavior has been removed. These strategies relate to the use of dialectical behavior therapy, another useful technique. DBT provides ways to tolerate distress and regulate emotions, both of which are challenging to someone with an addictive personality. DBT may not be the most effective treatment for all substance abusers, but there is evidence that it is helpful for most alcoholics and addicts, as well as in eating disorders, and those with co-occurring conditions.

Another form of treatment that has been considered for people with addictive personalities who tend towards substance abuse is medication. A medication called Disulfiram was created in 1947. This pill was used for alcoholics and would cause adverse effects if combined with alcohol. This medication is still used today but two others have been made to help treat alcohol dependence (Acamprosate and Naltrexone). Along with alcohol addictions, Naltrexone is also used for opioid addiction.

Although these medications have proven results in decreasing heavy drinking, doctors still have to consider the patients' health and the risky side effects when prescribing these medications.

Psychiatrist Kantor suggests a treatment approach using psychodynamic, supportive, cognitive, behavioral and interpersonal therapeutic methods. These methods apply to both the Passive–aggressive person and their target victim.

Personality development disorders usually need a complex and multi-dimensional treatment approach (Adam & Breithaupt-Peters, 2010). Since the problems are complex, treatment needs to affect the conditions in all impaired functional and social areas. Both educational and therapeutic methods are helpful and problem and strength based approaches work hand in hand. Parents need to be included as well as the school environment. Treatment methods need to be flexible and adjustable to the individual situation. Even elements of social work can be helpful when supporting the families and in some cases medication might be necessary. When suicidal behaviors or self-injuries are prominent treatment might best be done in a hospital.

For some personality development disorders (e.g. borderline personality disorder) treatment methods from adults can be adapted (e.g. dialectical behavior therapy, Miller et a., 2006).

Narcissistic personality disorder is rarely the primary reason for people seeking mental health treatment. When people with NPD enter treatment, it is typically prompted by life difficulties or to seek relief from another disorder, such as major depressive disorder, substance use disorders, bipolar disorder, or eating disorders, or at the insistence of relatives and friends. This is partly because individuals with NPD generally have poor insight and fail to recognize their perception and behavior as inappropriate and problematic due to their very positive self-image.

Treatment for NPD is centered around psychotherapy. In the 1960s, Heinz Kohut and Otto Kernberg challenged the conventional wisdom of the time by outlining clinical strategies for using psychoanalytic psychotherapy with clients with NPD that they claimed were effective in treating the disorder. Contemporary treatment modalities commonly involve transference-focused, metacognitive, and schema-focused therapies. Some improvement might be observed through the treatment of symptoms related to comorbid disorders with psychopharmaceuticals, but , according to Elsa Ronningstam, psychologist at Harvard Medical School, "Alliance building and engaging the patient's sense of agency and reflective ability are essential for change in pathological narcissism."

Pattern change strategies performed over a long period of time are used to increase the ability of those with NPD to become more empathic in everyday relationships. To help modify their sense of entitlement and self-centeredness schema, the strategy is to help them identify how to utilize their unique talents and to help others for reasons other than their own personal gain. This is not so much to change their self-perception of their "entitlement" feeling but more to help them empathize with others. Another type of treatment would be temperament change. Psychoanalytic psychotherapy may be effective in treating NPD, but therapists must recognize the patient's traits and use caution in tearing down narcissistic defenses too quickly. Anger, rage, impulsivity, and impatience can be worked on with skill training. Therapy may not be effective because patients may receive feedback poorly and defensively. Anxiety disorders and somatoform dysfunctions are prevalent but the most common would be depression.

Group treatment has its benefits as the effectiveness of receiving peer feedback rather than the clinician's may be more accepted, but group therapy can also contradict itself as the patient may show "demandingness, egocentrism, social isolation and withdrawal, and socially deviant behavior". Researchers originally thought group therapy among patients with NPD would fail because it was believed that group therapy required empathy that NPD patients lack. However, studies show group therapy does hold value for patients with NPD because it lets them explore boundaries, develop trust, increase self-awareness, and accept feedback. Relationship therapy stresses the importance of learning and applying four basic interpersonal skills: "...effective expression, empathy, discussion and problem solving/conflict resolution". Marital/relationship therapy is most beneficial when both partners participate.

No medications are indicated for treating NPD, but may be used to treat co-occurring mental conditions or symptoms that may be associated with it such as depression, anxiety, and impulsiveness if present.

The effectiveness of psychotherapeutic and pharmacological interventions in the treatment of narcissistic personality disorder has yet to be systematically and empirically investigated. Clinical practice guidelines for the disorder have not yet been created, and current treatment recommendations are largely based on theoretical psychodynamic models of NPD and the experiences of clinicians with afflicted individuals in clinical settings.

The presence of NPD in patients undergoing psychotherapy for the treatment of other mental disorders is associated with slower treatment progress and higher dropout rates.

Treatment for perfectionism can be approached from many therapeutic directions. Some examples of psychotherapy include: cognitive-behavioral therapy (the challenging of irrational thoughts and formation of alternative ways of coping and thinking), psychoanalytic therapy (an analysis of underlying motives and issues), group therapy (where two or more clients work with one or more therapists about a specific issue, this is beneficial for those who feel as if they are the only one experiencing a certain problem), humanistic therapy (person-centered therapy where the positive aspects are highlighted), and self-therapy (personal time for the person where journaling, self-discipline, self-monitoring, and honesty with self are essential). Cognitive-behavioral therapy has been shown to successfully help perfectionists in reducing social anxiety, public self-consciousness, and perfectionism. By using this approach, a person can begin to recognize his or her irrational thinking and find an alternative way to approach situations. Cognitive-behavioral therapy is intended to help the person understand that it is okay to make mistakes sometimes and that those mistakes can become lessons learned.

There is a general lack of consensus in the diagnosis and treatment of DID and research on treatment effectiveness focuses mainly on clinical approaches described in case studies. General treatment guidelines exist that suggest a phased, eclectic approach with more concrete guidance and agreement on early stages but no systematic, empirically-supported approach exists and later stages of treatment are not well described and have no consensus. Even highly experienced therapists have few patients that achieve a unified identity. Common treatment methods include an eclectic mix of psychotherapy techniques, including cognitive behavioral therapy (CBT), insight-oriented therapies, dialectical behavioral therapy (DBT), hypnotherapy and eye movement desensitization and reprocessing (EMDR). Medications can be used for comorbid disorders or targeted symptom relief. Some behavior therapists initially use behavioral treatments such as only responding to a single identity, and then use more traditional therapy once a consistent response is established. Brief treatment due to managed care may be difficult, as individuals diagnosed with DID may have unusual difficulties in trusting a therapist and take a prolonged period to form a comfortable therapeutic alliance. Regular contact (weekly or biweekly) is more common, and treatment generally lasts years—not weeks or months. Sleep hygiene has been suggested as a treatment option, but has not been tested. In general there are very few clinical trials on the treatment of DID, none of which were randomized controlled trials.

Therapy for DID is generally phase oriented. Different alters may appear based on their greater ability to deal with specific situational stresses or threats. While some patients may initially present with a large number of alters, this number may reduce during treatment—though it is considered important for the therapist to become familiar with at least the more prominent personality states as the "host" personality may not be the "true" identity of the patient. Specific alters may react negatively to therapy, fearing the therapist's goal is to eliminate the alter (particularly those associated with illegal or violent activities). A more realistic and appropriate goal of treatment is to integrate adaptive responses to abuse, injury or other threats into the overall personality structure. There is debate over issues such as whether exposure therapy (reliving traumatic memories, also known as abreaction), engagement with alters and physical contact during therapy are appropriate and there are clinical opinions both for and against each option with little high-quality evidence for any position.

Brandt et al., noting the lack of empirical studies of treatment effectiveness, conducted a survey of 36 clinicians expert in treating dissociative disorder (DD) who recommended a three-stage treatment. They agreed that skill building in the first stage is important so the patient can learn to handle high risk, potentially dangerous behavior, as well as emotional regulation, interpersonal effectiveness and other practical behaviors. In addition, they recommended "trauma-based cognitive therapy" to reduce cognitive distortions related to trauma; they also recommended that the therapist deal with the dissociated identities early in treatment. In the middle stage, they recommended graded exposure techniques, along with appropriate interventions as needed. The treatment in the last stage was more individualized; few with DD became integrated into one identity.

The International Society for the Study of Trauma and Dissociation has published guidelines to phase-oriented treatment in adults as well as children and adolescents that are widely used in the field of DID treatment. The first phase of therapy focuses on symptoms and relieving the distressing aspects of the condition, ensuring the safety of the individual, improving the patient's capacity to form and maintain healthy relationships, and improving general daily life functioning. Comorbid disorders such as substance abuse and eating disorders are addressed in this phase of treatment. The second phase focuses on stepwise exposure to traumatic memories and prevention of re-dissociation. The final phase focuses on reconnecting the identities of disparate alters into a single functioning identity with all its memories and experiences intact.

A study was conducted with the goal of developing an "expertise-based prognostic model for the treatment of complex posttraumatic stress disorder (PTSD) and dissociative identity disorder (DID)". Researchers constructed a two-stage survey and factor analyses performed on the survey elements found 51 factors common to complex PTSD and DID. The authors concluded from their findings: "The model is supportive of the current phase-oriented treatment model, emphasizing the strengthening of the therapeutic relationship and the patient's resources in the initial stabilization phase. Further research is needed to test the model's statistical and clinical validity."

The management and treatment of personality disorders can be a challenging and controversial area, for by definition the difficulties have been enduring and affect multiple areas of functioning. This often involves interpersonal issues, and there can be difficulties in seeking and obtaining help from organizations in the first place, as well as with establishing and maintaining a specific therapeutic relationship. On the one hand, an individual may not consider themselves to have a mental health problem, while on the other, community mental health services may view individuals with personality disorders as too complex or difficult, and may directly or indirectly exclude individuals with such diagnoses or associated behaviors. The disruptiveness that people with personality disorders can create in an organisation makes these, arguably, the most challenging conditions to manage.

Apart from all these issues, an individual may not consider their personality to be disordered or the cause of problems. This perspective may be caused by the patient's ignorance or lack of insight into their own condition, an ego-syntonic perception of the problems with their personality that prevents them from experiencing it as being in conflict with their goals and self-image, or by the simple fact that there is no distinct or objective boundary between 'normal' and 'abnormal' personalities. Unfortunately, there is substantial social stigma and discrimination related to the diagnosis.

The term 'personality disorder' encompasses a wide range of issues, each with a different level of severity or disability; thus, personality disorders can require fundamentally different approaches and understandings. To illustrate the scope of the matter, consider that while some disorders or individuals are characterized by continual social withdrawal and the shunning of relationships, others may cause "fluctuations" in forwardness. The extremes are worse still: at one extreme lie self-harm and self-neglect, while at another extreme some individuals may commit violence and crime. There can be other factors such as problematic substance use or dependency or behavioral addictions. A person may meet the criteria for multiple personality disorder diagnoses and/or other mental disorders, either at particular times or continually, thus making coordinated input from multiple services a potential requirement.

Therapists in this area can become disheartened by lack of initial progress, or by apparent progress that then leads to setbacks. Clients may be perceived as negative, rejecting, demanding, aggressive or manipulative. This has been looked at in terms of both therapist and client; in terms of social skills, coping efforts, defense mechanisms, or deliberate strategies; and in terms of moral judgments or the need to consider underlying motivations for specific behaviors or conflicts. The vulnerabilities of a client, and indeed a therapist, may become lost behind actual or apparent strength and resilience. It is commonly stated that there is always a need to maintain appropriate professional personal boundaries, while allowing for emotional expression and therapeutic relationships. However, there can be difficulty acknowledging the different worlds and views that both the client and therapist may live with. A therapist may assume that the kinds of relationships and ways of interacting that make them feel safe and comfortable have the same effect on clients. As an example of one extreme, people who may have been exposed to hostility, deceptiveness, rejection, aggression or abuse in their lives, may in some cases be made confused, intimidated or suspicious by presentations of warmth, intimacy or positivity. On the other hand, reassurance, openness and clear communication are usually helpful and needed. It can take several months of sessions, and perhaps several stops and starts, to begin to develop a trusting relationship that can meaningfully address a client's issues.