Woman shares excitement over not needing walker.

Acceptance and commitment therapy (ACT) is an evidence-based psychological intervention that teaches individuals to develop psychological flexibility — the ability to stay present with difficult thoughts and emotions while taking meaningful action aligned with personal values. Unlike traditional approaches that focus on symptom reduction, ACT helps people live fuller, more vital lives even in the presence of psychological pain.

Recent research shows ACT has a strong evidence base across diverse psychological and behavioral problems, with a meta-analysis of 65 studies (n=5,283) finding a moderate effect size (Hedges's g = 0.72) compared to control conditions. ACT enhances psychological flexibility by fostering acceptance of thoughts and emotions, promoting mindfulness practices, and encouraging engagement in value-based actions, with accumulating evidence supporting its efficacy across various psychiatric disorders.

Table of Contents

  • What Is ACT?
  • History and Development
  • Understanding the Theory Behind ACT
  • Six Core Processes of Psychological Flexibility
  • How ACT Differs from Other Therapies
  • Conditions Treated with ACT
  • What to Expect in ACT Treatment
  • Finding an ACT Therapist
  • Frequently Asked Questions
  • How Therapy Can Help

What Is ACT?

Acceptance and commitment therapy (pronounced as the word "act") is a form of psychotherapy that combines mindfulness strategies with behavior-change techniques to help people develop psychological flexibility. ACT primarily aims to increase psychological flexibility in order to live a more fulfilling and meaningful life.

ACT rests on the fundamental premise that pain, grief, disappointment, illness, and anxiety are inevitable features of human life, with the therapeutic goal of helping individuals productively adapt to these types of challenges by developing greater psychological flexibility rather than engaging in counterproductive attempts to eliminate or suppress undesirable experiences. This is achieved through committed pursuit of valued life areas and directions, even in the face of the natural desire to escape or avoid painful and troubling experiences, emotions, and thoughts.

The approach is:

  • Transdiagnostic — applies to more than one condition
  • Process-focused — targets underlying psychological processes rather than specific symptoms
  • Values-based — emphasizes living according to what matters most to you
  • Flexibly delivered — can be adapted to various formats and settings

History and Development

ACT emerged in the late 1990s as part of the "third wave" of cognitive-behavioral therapies. Steven C. Hayes and colleagues developed ACT based on Relational Frame Theory (RFT), a behavioral account of human language and cognition.

The development of ACT was motivated by several factors:

  • Recognition that attempts to control or eliminate difficult thoughts and feelings often backfire
  • Growing evidence for the role of experiential avoidance in psychological problems
  • Need for treatments that address the full human experience, not just symptom reduction
  • Desire to integrate mindfulness and acceptance with behavioral activation

Since its inception, ACT has been evaluated in over 900 randomized trials to date, addressing an extremely broad range of psychological and behavioral problems and disorders. Multiple comprehensive treatment manuals have been developed, and ACT is recognized by the Substance Abuse and Mental Health Services Administration (SAMHSA) and was added to their National Registry of Evidence-Based Programs and Practices in 2010.

Understanding the Theory Behind ACT

Psychological Flexibility: The Core of ACT

Psychological inflexibility is defined as the rigid responding to stimuli (e.g., unpleasant thoughts and feelings) that interferes with well-being and valued actions. It is the treatment target in acceptance and commitment therapy (ACT). Despite the centrality of the link between inflexibility and well-being to ACT theory, developing flexibility is the primary goal.

Psychological flexibility according to ACT can be defined as "the tendency to respond to situations in ways that facilitate valued goal pursuit," which includes being in touch with the present moment and the feelings it comes with, without fighting them unnecessarily. Psychological flexibility becomes especially important in challenging situations and is closely linked to resilience.

The Role of Language and Cognition

ACT is based on Relational Frame Theory (RFT), which suggests that human language naturally creates suffering. Our ability to relate events symbolically means we can:

  • Re-experience past pain through memory
  • Anticipate future threats through imagination
  • Compare ourselves unfavorably to ideals
  • Get caught up in unhelpful stories about ourselves

Based on Relational Frame Theory, ACT illuminates the ways that language entangles clients into futile attempts to wage war against their own inner lives. Through metaphor, paradox, and experiential exercises, clients learn how to make healthy contact with thoughts, feelings, memories, and physical sensations that have been feared and avoided.

Six Core Processes of Psychological Flexibility

ACT targets six interrelated processes that together create psychological flexibility:

1. Contact with the Present Moment (Mindfulness)

Being psychologically present and aware of the current moment without judgment. This involves:

  • Noticing thoughts, feelings, and sensations as they arise
  • Observing without immediately reacting
  • Practicing sustained, flexible attention

2. Acceptance

Acceptance is the ability to allow internal and external experience to occur instead of fighting or avoiding the experience. This means:

  • Opening up to difficult emotions
  • Letting go of the struggle against unwanted thoughts
  • Making room for the full range of human experience

3. Cognitive Defusion

Creating distance from thoughts to reduce their automatic influence. Techniques include:

  • Observing thoughts as mental events, not facts
  • Using metaphors to see thoughts differently
  • If someone thinks, "I'm a terrible person," that person might be asked to instead say, "I am having the thought that I'm a terrible person." This effectively separates the person from the cognition, thereby stripping it of its negative charge

4. Self-as-Context

Developing a transcendent sense of self that is distinct from thoughts, feelings, and roles. This involves:

  • Recognizing the observing self that notices all experiences
  • Understanding you are not your thoughts or feelings
  • Cultivating a stable sense of perspective

5. Values

Clarifying what is most important and meaningful in life. Values:

  • Provide direction and motivation for behavior change
  • Are freely chosen life directions, not goals
  • Guide decision-making and priority-setting
  • Remain important even when difficult to pursue

6. Committed Action

Taking concrete steps guided by values, even when difficult. This includes:

  • Setting specific, achievable goals aligned with values
  • Persisting through obstacles and setbacks
  • Building patterns of effective action
  • Adjusting strategies while maintaining value direction

How ACT Differs from Other Therapies

ACT vs. Cognitive Behavioral Therapy (CBT)

While both are evidence-based approaches, they differ in key ways:

CBT focuses on:

  • Changing dysfunctional thoughts
  • Reducing symptom frequency and intensity
  • Teaching thought-challenging techniques
  • Eliminating negative emotions

ACT focuses on:

  • Changing relationship to thoughts
  • Increasing psychological flexibility
  • Teaching mindfulness and acceptance
  • Living meaningfully despite difficult emotions

A review of meta-analyses concluded that ACT is equally effective as established evidence-based treatments (e.g., CBT) and superior to inactive control conditions (e.g., placebo or waitlist) and treatment as usual (TAU).

Integration with Other Approaches

ACT can be integrated with other evidence-based treatments:

  • Behavioral activation for depression
  • Exposure therapy for anxiety disorders
  • Skills training for emotion regulation
  • Motivational interviewing for ambivalence about change

Conditions Treated with ACT

Research demonstrates ACT's effectiveness across a wide range of conditions:

Mental Health Conditions

Depression

A meta-analysis found ACT could effectively alleviate depressive symptoms in adolescents, with 25 studies published between 2009 and 2024 including 2,352 participants. Another study found ACT had a significant effect on depressive symptoms (SMD=-0.69, 95% CI: -1.06 to -0.32, P<0.001) among individuals with depression.

Anxiety Disorders

Treating anxiety disorders with acceptance and commitment therapy (ACT) has a strong theoretical and empirical foundation. Meta-analyses show that ACT can reduce anxiety symptoms and psychological inflexibility while improving mindfulness, pain acceptance, and psychological flexibility.

Eating Disorders

ACT conceptualizes eating disorders (EDs) as rigid attempts to solve the problem of human suffering through food, eating, or weight control. Case formulation and intervention is based on functional assessment of ED behaviors and informed by common patterns of psychological inflexibility. Studies have shown "large reductions" of eating disorder behavior and overall better cognitive functioning when compared with cognitive behavioral therapy (CBT).

Substance Use Disorders

ACT has shown to be an intervention with great success in the reduction of various mental disorders and substance use disorders (SUDs). The core of ACT when used in SUD treatment is guiding people to accept the urges and symptoms associated with substance misuse (acceptance) and use psychological flexibility and value-based interventions to reduce those urges and the symptoms (commitment). A meta-analysis found ACT increased the odds of abstinence at end of treatment and at short-term follow-up, demonstrating higher abstinence rates than CBT conditions.

Psychosis

Research shows ACT is feasible and acceptable for individuals at risk for psychosis or with a first psychotic episode, delivered both in-person and through digital formats.

Physical Health Conditions

Chronic Pain

An overview of systematic reviews found ACT can reduce depression symptoms, anxiety symptoms, psychological inflexibility, and pain catastrophizing; and can improve mindfulness, pain acceptance, and psychological flexibility. At three-month follow-up, ACT can reduce depression symptoms and psychological inflexibility, as well as improve pain-related functioning and psychological flexibility. At six-month follow-up, ACT can improve mindfulness, pain-related functioning, pain acceptance, psychological flexibility, and quality of life.

Cancer

A systematic review and meta-analysis of 16 RCTs from 6 countries with 711 participants found ACT significantly improved psychological flexibility, with patients' acceptance and related psychological distress, including anxiety and depression, significantly improving.

What to Expect in ACT Treatment

Initial Assessment and Values Clarification

Usually, at the start of treatment, a therapist will work with a patient to clarify their goals and values. This can help a patient cultivate clarity around what they want and help them begin to understand how their thoughts or behaviors may interfere with the pursuit of these goals.

Treatment Components

ACT treatment typically includes:

1. Experiential exercises — Activities designed to increase psychological flexibility

2. Metaphors and stories — To illustrate concepts and shift perspective

3. Mindfulness practices — Both formal and informal exercises

4. Values exploration — Identifying what matters most

5. Behavioral activation — Taking steps toward valued living

6. Between-session practice — Applying skills in daily life

Treatment Format and Duration

ACT can be delivered in various formats:

  • Individual therapy (typically 8-20 sessions)
  • Group therapy
  • Intensive workshops or retreats
  • Self-help with therapist support
  • Digital and online formats
  • Integrated approaches combining ACT group psychotherapy, occupational therapy, art therapy, movement therapy, mindfulness training, and individual sessions

Research indicates a greater number of ACT sessions increased long-term abstinence rates, though benefits can be seen with brief interventions.

Finding an ACT Therapist

Professional Training and Qualifications

There is no ACT certification process. ACBS, as a community, has decided to forego this, as it could create a hierarchical and closed process which would be antithetical to our values. Rather, we aim to foster an open, self-critical, mutually supportive community which, working together, builds a progressive psychology more adequate to the challenges of human suffering. There is no such thing as an officially certified ACT therapist.

However, quality training is available through:

  • Peer-reviewed ACT trainers through ACBS who use a multi-faceted peer-review process taken very seriously
  • Graduate programs with ACT emphasis
  • Continuing education workshops
  • Online training programs
  • Supervision and consultation groups

How to Find an ACT Provider

1. ACBS Therapist Registry You can find all the professionals listed as an ACT therapist on the Association for Contextual Behavioral Science (ACBS) website. These are ACBS members who have identified themselves as an ACT therapist and are available for consultation.

2. Psychology Department Referrals Contact the psychology, social work, or psychiatry department at a nearby college or university. Faculty members who are experts in behavior therapy or cognitive behavior therapy may know about local ACT therapists.

3. Professional Organizations

  • Association for Behavioral and Cognitive Therapies (ABCT)
  • State psychological associations
  • Local mental health provider networks

1. Insurance Provider Directories Check with your insurance company for covered providers who list ACT as a specialty.

Questions to Ask Potential Therapists

  • What is your training and experience with ACT?
  • How do you typically use ACT in treatment?
  • Have you treated my specific condition with ACT?
  • What does a typical session look like?
  • How do you measure progress in therapy?

Frequently Asked Questions

Is ACT effective for my condition?

ACT is equally effective as established evidence-based treatments and superior to inactive control conditions and treatment as usual. ACT (including alternative, scalable formats like digital self-help, as well as its delivery by non-mental health professionals) can be used to effectively treat a wide range of psychological problems. Research shows particular effectiveness for anxiety, depression, chronic pain, substance use disorders, and eating disorders.

How is ACT different from just "accepting" problems?

ACT is not about passive resignation or giving up. Instead, acceptance in ACT means:

  • Acknowledging reality without unnecessary struggle
  • Making room for difficult experiences when avoiding them causes problems
  • Freeing up energy to focus on what you can control
  • Taking effective action guided by your values

Will I have to share my deepest secrets?

ACT focuses more on how you relate to your thoughts and feelings than on their specific content. While sharing can be helpful, the emphasis is on developing skills to handle whatever shows up in your life, not necessarily discussing every detail of your history.

How long does ACT treatment take?

Treatment length varies based on individual needs and goals. Some people benefit from brief interventions (4-6 sessions), while others engage in longer-term therapy. Research examining ACT across different formats found effects in treatments ranging from self-help to intensive therapy.

Can ACT be combined with medication?

Yes, ACT works well alongside psychiatric medication. The therapy can help you:

  • Develop skills for managing symptoms
  • Clarify values to guide treatment decisions
  • Build a meaningful life while managing a mental health condition
  • Address any concerns about medication through open discussion with your providers

Is ACT religious or spiritual?

While ACT incorporates mindfulness practices, it is not inherently religious or spiritual. The approach is based on psychological science and can be adapted to fit with any belief system or worldview.

How Therapy Can Help

Taking the first step toward therapy can feel daunting, but support is available. ACT offers a compassionate, evidence-based approach that honors your full experience while helping you build the life you want to live.

If you're struggling with difficult thoughts, emotions, or life circumstances, a therapist trained in ACT can help you:

  • Develop psychological flexibility to handle life's challenges
  • Clarify what matters most to you
  • Take meaningful action despite obstacles
  • Build resilience and vitality
  • Create lasting positive change

Find a Therapist: Use the GoodTherapy directory to connect with qualified mental health professionals in your area who can help you explore whether ACT might be right for you. You can search by location, insurance, specialty, and therapeutic approach to find the best match for your needs.

Remember, seeking help is a sign of strength, not weakness. With the right support, you can develop the skills to live a rich, full, and meaningful life — even in the presence of difficult thoughts and feelings.

References:

  1. American Psychological Association (APA). (2023). Evidence-based practice in psychology. Retrieved from https://www.apa.org/practice/resources/evidence
  2. Arch, J.J., Finkelstein, L.B., & Nealis, M.S. (2025). Acceptance and commitment therapy (ACT) for anxiety disorders. Psychiatric Clinics of North America, 48(3), 443-456. https://doi.org/10.1016/j.psc.2025.02.003
  3. Association for Contextual Behavioral Science (ACBS). (2024). ACT certification and training standards. Retrieved from https://contextualscience.org/act_certification
  4. Centers for Disease Control and Prevention (CDC). (2023). Mental health for all. Retrieved from https://www.cdc.gov/disability-and-health/articles-documents/mental-health.html
  5. de Waal, N.M., Laarhoven, L.M., Scharloo, M., & Wolterbeek, R. (2025). The efficacy of acceptance and commitment therapy for transitional-age youth: A meta-analysis. Clinical Child and Family Psychology Review, 28. https://doi.org/10.1007/s10567-025-00543-5
  6. González-Fernández, S., & Fernández-Rodríguez, C. (2024). Effectiveness of acceptance and commitment therapy for addictive behaviors: A systematic review and meta-analysis. Journal of Contextual Behavioral Science, 33. https://doi.org/10.1016/j.jcbs.2024.100801
  7. Latella, D., Marafioti, G., Formica, C., Calderone, A., La Fauci, E., Foti, A., Calabrò, R.S., & Filippello, G. (2025). The role of acceptance and commitment therapy in improving social functioning among psychiatric patients: A systematic review. Healthcare (Basel), 13(13), 1587. https://doi.org/10.3390/healthcare13131587
  8. Levin, M.E., Krafft, J., & Twohig, M.P. (2024). An overview of research on acceptance and commitment therapy. Psychiatric Clinics of North America, 47(2), 419-431. https://doi.org/10.1016/j.psc.2024.02.007
  9. López-Pinar, C., Lara-Merín, L., & Macías, J. (2025). Process of change and efficacy of acceptance and commitment therapy (ACT) for anxiety and depression symptoms in adolescents: A meta-analysis of randomized controlled trials. Journal of Affective Disorders, 368, 633-644. https://doi.org/10.1016/j.jad.2024.09.076
  10. Martinez-Calderon, J., García-Muñoz, C., Rufo-Barbero, C., Matias-Soto, J., & Cano-García, F.J. (2024). Acceptance and commitment therapy for chronic pain: An overview of systematic reviews with meta-analysis of randomized clinical trials. The Journal of Pain, 25(3), 595-617. https://doi.org/10.1016/j.jpain.2023.09.013
  11. Merwin, R.M., Moskovich, A.A., & Scheiber, F. (2025). Acceptance and commitment therapy for eating disorders. Psychiatric Clinics of North America, 48(3), 521-535. https://doi.org/10.1016/j.psc.2025.02.007
  12. National Institute of Mental Health (NIMH). (2024). Mental health information. Retrieved from https://www.nimh.nih.gov/
  13. Navarrete, J., Rodríguez-Freire, C., Sanabria-Mazo, J.P., Martínez-Rubio, D., McCracken, L.M., et al. (2025). Assessing psychological flexibility and inflexibility in chronic pain using the Multidimensional Psychological Flexibility Inventory (MPFI). European Journal of Pain, 29(1), e4704. https://doi.org/10.1002/ejp.4704
  14. Ong, C.W., Barthel, A.L., & Hofmann, S.G. (2024). The relationship between psychological inflexibility and well-being in adults: A meta-analysis of the Acceptance and Action Questionnaire (AAQ). Behavior Therapy, 55(1), 26-41. https://doi.org/10.1016/j.beth.2023.05.007
  15. P, A.S., & S, G. (2025). Acceptance and commitment therapy and psychological well-being: A narrative review. Cureus, 17(1), e77705. https://doi.org/10.7759/cureus.77705
  16. Rutschmann, R., Romanczuk-Seiferth, N., & Gloster, A. (2024). Increasing psychological flexibility is associated with positive therapy outcomes following a transdiagnostic ACT treatment. Frontiers in Psychiatry, 15, 1403718. https://doi.org/10.3389/fpsyt.2024.1403718
  17. Saavedra, J.M., & Muñoz-Martínez, A.M. (2025). Psychological flexibility and inflexibility of university students: An in-depth qualitative study. Behavioral Sciences, 14(7). https://doi.org/10.3390/bs14070561
  18. Substance Abuse and Mental Health Services Administration (SAMHSA). (2024). National Survey on Drug Use and Health (NSDUH) 2023 data release. Center for Behavioral Health Statistics and Quality. Retrieved from https://www.samhsa.gov/data/data-we-collect/nsduh-national-survey-drug-use-and-health/national-releases/2023
  19. van Aubel, E., Vaessen, T., Uyttebroek, L., Steinhart, H., Beijer-Klippel, A., Batink, T., et al. (2024). Acceptance and commitment therapy for individuals at risk for psychosis or with a first psychotic episode: A qualitative study on patients' perspectives. Early Intervention in Psychiatry, 18(2), 122-131. https://doi.org/10.1111/eip.13442
  20. Yu, Y., Zhao, J., Yin, L., Qu, X., Zhang, Y., Cheng, Z., & Chen, X. (2025). Effect of acceptance and commitment therapy for adolescent depression: A meta-analysis. Frontiers in Psychiatry, 16, 1506822. https://doi.org/10.3389/fpsyt.2025.1506822