Acceptance and Commitment Therapy

An Overview of the Model and Treatment

Vasiliki Christodoulou

Vasiliki Christodoulou describes how Acceptance and Commitment Therapy can offset what is arguably a primary route to psychopathology – our ability to create and use language


Acceptance and Commitment Therapy (ACT) is a contextual therapy that emerged from within the family of cognitive-behavioural psychotherapies. ACT provides a trans-theoretical model that accommodates cognitive, behavioural, existential and humanistic elements; its composition appeals to practitioners from various backgrounds. I encountered ACT whilst practicing Cognitive Behavioural Therapy (CBT); at this stage I felt that standard CBT protocols were lacking in emotional regulation skills and felt stuck in attempts to ‘modify’ clients’ thinking. ACT offered an alternative set of therapeutic goals that seemed more workable.

ACT maintains that our biggest human advantage, our ability to create and use language, is also the route of psychopathology since it is through language that we re-experience painful histories and become stuck in unhealthy pursuits (Hayes, Strosahl, & Wilson, 1999). The problem begins when thoughts come to rigidly guide behaviour, irrespective of conflicting experiential input (Hayes, Luoma, Bond, Masuda & Lillis, 2006). For example, people might avoid challenges because they literally believe their thoughts (ie ‘I can’t do it because I am incompetent’). In a Western culture that emphasizes reason-giving (‘Why can’t you do it?’) people become attached to self-descriptions and find it hard to act differently. The process of experiencing thoughts as reality, rather than as the on-going process of thinking, is coined cognitive fusion and is believed to trap people in stagnant behavioural patterns (Hayes et al, 2006).

ACT identifies that our societal discourse idealises positive emotions. A quick look at any magazine will reveal hundreds of ‘quick fix’ solutions that are guaranteed to offer happiness. Yet, more challenging emotions are ever-present in a world plagued by natural disasters, accidents, crime, financial and relational insecurities. Such uncomfortable feelings are often seen as ‘bad’ and are accompanied by efforts to avoid or stop them (Hayes et al, 1999). ACT uses the term ‘experiential avoidance’ to describe people’s attempts to control unwanted internal experiences (Hayes, Wilson, Gifford, Follette & Strosahl, 1996). Ironically, attempts to suppress distressing internal events may actually amplify them (eg Wegner, 1997) while other avoidance strategies (eg alcohol, drug use, procrastination) can have unhelpful long-term consequences. Indeed, research shows that experiential avoidance is associated with increased risk of psychopathology (Hayes & Gifford, 1997).

In ACT’s model, experiential avoidance and cognitive fusion are two central mechanisms that underpin psychological rigidity which is characterised by heavy attachment to one’s own cognitions and subsequent behavioural inflexibility (Hayes et al, 2006, p. 6.). For example, an individual may come to avoid sharing moments of weakness with their spouse to block feelings of vulnerability although they may value relational closeness.

ACT’s model of psychopathology

ACT’s goal is to increase psychological flexibility – the ability to live life fully, in touch with the present moment – and modify behaviour based on real-life experience and long-term values (Hayes et al, 2006). Psychological flexibility is associated with a lower likelihood of developing a psychological disorder (Donaldson-Feilder & Bond, 2004) and is cultivated through six interconnected processes

Image 1
ACT’s model of psychological flexibility (Hayes et al 2006)

The concept of acceptance has long been featured in religious philosophies and humanistic models (Barnes-Holmes, Cochrane, Barnes-Holmes, Stewart, & Hugh, 2004). ACT suggests abandoning efforts to control private events and focuses on changing the relationship one has with internal experiences (Luoma, Hayes, & Walser, 2007). Clients are encouraged to experience emotions and thoughts as natural events and not become consumed by them (Blackledge & Hayes, 2001). It is believed that when an emotion is no longer a cue for avoidance or suppression its importance might even gradually dissipate (Hayes & Wilson, 1994). Interestingly, research participants who had been instructed to approach physical pain or anxiety within an acceptance rationale were able to contain these experiences for longer periods of time than those using control-based strategies (eg Eifert & Heffner, 2003; Gutierrez, Luciano, Rodriguez, & Fink, 2004).

Defusion is the ability to ‘step back’ and acknowledge thoughts as the product of one’s mind. ACT posits that attempts to change the content of thoughts are problematic since focusing on them, even in the context of cognitive restructuring, can increase their salience (Luoma et al, 2007). ACT aims to create new contexts for experiencing thoughts (Hayes et al, 2006). For instance, instead of experiencing a thought in the context of literality where each thought is treated as a ‘true fact’, clients learn to experience thoughts in a context of deliteratisation where a thought is viewed as no more than a symbol or the product of one’s history (Hayes et al, 1999). Therefore the problem is not ‘what we think’ but the type of relationship we have with our thoughts. Indeed, Masuda, Hayes, Sackett, and Twohig (2004) found that rapidly repeating self-relevant negative thoughts out loud (a defusion exercise) reduced associated distress more than comparison interventions like distraction or thought control.

ACT teaches on-going, non-judgemental present-moment awareness. As humans we spend our lives in a cognitively constructed world of worry, rumination, planning and daydreaming. By becoming more attentive in the present moment we can gain invaluable experiential information on what is working well and make skilful behavioural choices (Hayes et al, 2006). Individuals are also encouraged to gain perspective on rigidly defining themselves based on the content of their thoughts and are taught to activate a sense of self as context (Hayes et al, 2006). While growing up, we become attached to certain stories about ourselves and this process creates a conceptualised self that contains beliefs and memories of ‘who I am’ (Hayes et al, 1999). Investing in these stories, albeit useful in some contexts, can also limit self-expression. In ACT one learns to contact a more stable part of the self; that is, the perspective that one takes in experiencing the world (the “I” that observes our experience). Learning how to contact this self-as-context is crucial as it indicates that there is an unthreatened locus from which one can cultivate acceptance.

ACT also emphasizes behavioural change. Clients are asked to choose and pursue movement in meaningful life directions; these directions are referred to as values (Hayes et al, 1999). Valuing is done freely and sensitively and does not depend on what is thought of as ‘right’, ‘true’ or ‘logical’. The choice of values depends on what is significant and emotive for the individual. Values are dynamic patterns of action and are on-going, never-ending, and continuous. ACT also encourages the development of patterns of committed action. This entails pursuing ever-growing behavioural repertoires that are consistent with one’s values (Luoma et al, 2007). Individuals do not enter demanding situations intending eventually to experience a reduction in difficult emotions (as in a habituation paradigm) but are taught to approach challenges with openness, participating fully in their lives in view of what they value.

Therapeutic stages

ACT is a flexible model where the ordering of interventions depends on one’s formulation on the hexagon model. In actual practice interventions are introduced alongside each other since they often address overlapping processes. Image 2 presents an adapted formulation diagram as originally published by Hayes et al (2006).

Image 2
ACT’s model of psychological rigidity (adapted from Hayes et al, 2006)

A typical starting point in therapy is to undermine clients’ reliance on experiential control. Clients come to therapy believing that their emotions are harmful and the notion of acceptance is alien; their goal is identifying and eliminating the causes of negative affect. The task will be to highlight the limitations of experiential control (eg “What have you tried before? How has this worked for you so far?” Hayes et al, 1999). As the client begins to acknowledge the inherent challenges of achieving emotional control, the therapist infuses willingness for experiencing private events. One could make use of interventions such as mindfulness exercises where clients non-judgementally observe internal experiences. ACT makes frequent use of experiential exercises and metaphors and some representative examples are found in Table 1.

In order to develop acceptance it is also essential to notice the impact language can have on behaviour and emotions. The therapeutic task involves undermining cognitive fusion by creating a space between the thinker and the thought. One can make use of defusion exercises such as asking clients to label private events (eg ‘this is a judgement’, ‘this is an emotion’). Defusion is modelled by gently observing when the client appears to be fused with a thought (“Are you having this thought or are you buying this thought right now?” Hayes et al, 1999). Clients might also be gently directed back to the present moment when digressing to fused content (eg “Would you be willing to notice what is showing up for you physically and emotionally right now?”).

A sense of self-as-context is developed by asking clients to notice the part that is observing their experience (“Who is aware of your thoughts and bodily sensations right now?”). A commonly used metaphor is the ‘cloud and sky’ analogy where the ‘observing self’ (the blue sky) is presented as stable and having the capacity to contain transient internal experiences (Hayes & Strosahl, 2004).

It is fundamental that therapists invest time in activating valued living. In some cases values are evident and this can be done at the initial stages. However, when clients appear to be heavily fused with ‘conceptualised rules’ of how their lives ‘should be’, value clarification might need to be postponed. Clients are asked to consider what they would like their life to stand for and notice personal qualities that they would like to activate (Hayes et al, 1999). Building patterns of committed action involves identifying everyday actions that can be pursued in the context of one’s values.

Table 1
Examples of interventions used to target the six interrelated ACT processes

Who is ACT for?

ACT does not use diagnostic classification systems as it recognises limitations in uncovering common aetiologies for diagnostic syndromes (Hayes et al, 1996). The hexaflex model is used as a tool for a holistic formulation and treatment and it is considered broad enough to formulate a wide array of problems faced by individuals, organisations, and societies (Hayes & Strosahl, 2004). ACT has been found effective across different populations and for a range of problems in research studies. In a comprehensive meta-analysis Hayes et al (2006) reported that comparing ACT to other structured interventions resulted in a medium effect size in favour of ACT (at post .48 [n=456] and .63 [n=404] at follow-up) while studies that compared ACT to a control condition produced higher effect sizes (.99 at post-intervention [n=248] and .71 [n=176] at follow-up). ACT has also recently been listed by the United States Substance Abuse and Mental Health Services Administration as an empirically supported method (SAMHSA, 2010).

I have used ACT professionally in two contexts: in clinical work with clients in primary care psychotherapy settings, and as a preventative intervention for university students and academic staff in the United Kingdom. In terms of using ACT in a therapy context, I have found that the model allows for great flexibility and creativity in shaping the course of therapy and choice of interventions. In practice, clients often struggle with the idea of giving up efforts of controlling emotional distress but it is in this awkward moment that work starts. Instead of ignoring the realisation that there will be no ‘magical solutions’, we notice what comes up for the client (fear, disappointment, sadness) and for the therapist (apprehension, guilt, impotence). It is from here that fresh air enters the room. If therapy will not be about feeling better, what can it be about? What can life be about? For clients who have struggled with low mood and anxiety for years it can be refreshing to consider setting different goals for distress reduction whilst embarking on therapy.

I recall a client who avoided spending time alone with her son because, in those moments, she was plagued by thoughts of developing terminal illness. In what was a key moment, she noticed that she could experience fulfilling moments with her son in the presence of such thoughts while pursuing values of closeness and caring. Another client who suffered 25 years of trauma-related intrusive imagery noticed that by giving up efforts of controlling intrusions, he was able to reconnect with his creativity and compose music about his experience. A young woman who suffered from chronic low mood and unrelenting self-criticism came to see that she could observe her ‘critical voices’ and yet, she did not have to ‘be at their beck and call.’

In my experience ACT provides a meaningful and powerful therapy goal; developing the ability to notice internal experiences and not immediately react or jerk away but reflect on personal values and respond accordingly. Achieving this skill requires considerable investment of time and effort; clients are encouraged to practice mindfulness exercises and bring regular awareness to their present moment. Practicing ‘the skill of noticing’ can be demanding, especially for individuals who have been highly experientially avoidant. This is where genuine empathy and modelling from the therapist is essential.

I have also used ACT in research projects implemented in academic settings (Christodoulou, 2010). ACT is a very good model for use in prevention or brief intervention schemes as it does not patholologise problems but emphasizes the normality of suffering; we all have ‘minds’ that often get us into trouble. ACT can easily be delivered in a psycho-educational group format where participants consider the pros and cons of emotional avoidance and learn how to ‘step back’ and become flexible observers of their experience. Value clarification exercises can be particularly useful in this context; people often report that they have rarely questioned themselves on what is important in their lives. This type of exercise reveals a wide array of small value-based actions that one can incorporate in life.

ACT therapists are expected to ‘practice what they preach’ and attempt to model elements of psychological flexibility in their lives and in sessions (Strosahl, Hayes, Wilson, & Gifford, 2004). Giving up on attempts to lessen clients’ difficult emotions and abandoning efforts to ‘make sense’ of problems and discover solutions can be challenging task, especially for those used to having distress reduction as an end-goal. An ACT therapist seeks to cultivate openness and present-moment awareness especially when this involves contacting experiential pain., On reflection, I feel that ACT has influenced aspects of how I approach life; clarifying my own personal values has allowed me to make more informed choices while by learning to be more open and accepting of my experience (pleasant or unpleasant) I have been able to be more present and responsive with my family, friends and clients.

What do I do next?

The ACT community welcomes therapists from different orientations whatever their background. The emphasis is not on the type of techniques one uses – in fact, individualised metaphors and exercises are often developed in collaboration with clients. What is important is that the therapist is ready to abandon distress reduction as an end goal and is willing to pursue increasing psychological flexibility.

If you find this approach interesting and would like to read more about it there are many opportunities. ACT is affiliated with a website ( that offers free materials and advice. There are also many widely accessible published books as well as frequent workshops in the UK.


Dr Vasiliki Christodoulou is an HPC registered Counselling Psychologist experienced in delivering Acceptance and Commitment Therapy (ACT) group interventions in therapeutic, educational, and workplace settings. She is interested in evaluating the impact of brief, preventative ACT programmes on individuals’ wellbeing and personal resilience. Vasiliki is a provisionally accredited CBT therapist with expertise in delivering contextual and mainstream CBT in primary and secondary care. Currently, she is running a randomised controlled trial comparing the effectiveness of mindfulness-based interventions for mental health staff.


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Image: The Highlands September 075 by Michael Mosol


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