Wednesday, July 26, 2023

Psychological Flexibility

Steven Hayes 

Why does psychotherapy work? Until relatively recently, many scientists studying methods of improving mental and behavioral health have delayed answering that question. Instead, they argued, it’s better first to ask if a method works, and when we know that it does, then we can ask why.

It’s not an irrational strategy, but as the decades went by thousands upon thousands of studies poured out an ever expanding list of interventions, many of which might look different but actually work by the same processes or mechanisms. The lists of “evidence-based therapies” maintained by scientific bodies or governmental agencies did not require any knowledge of processes of change, so methods proliferated. Sometimes quite outlandish theories were put forward by therapy advocates and as long as the bottom line outcomes were better than a control condition, the methods went on those lists — emboldening advocates to claim their theories were correct.

Maybe. Maybe not. Outcomes alone can’t tell you. You have to answer the “why” question.

Gradually statistical methods that identify important pathways of change — that answer the why question — became more common in psychotherapy research. The best known and most widely used method is called “mediational analysis”. Mediation applies when a) a treatment changes a near term process more so than a control condition, b) that process relates to outcomes in both groups, and pulling out that “a to b” pathway significantly reduces the impact of treatment on outcome. It’s not a perfect method but it’s a place to start and the body of studies in that area are now large enough to do a comprehensive tally. About five years ago, my colleagues (Stefan Hofmann then at Boston University; Joe Ciarrochi at Australian Catholic University; and our associates Baljinder Sahdra and Fred Chin) and I decided to look at all successful mediational studies ever done on any psychosocial intervention in a randomized controlled trial targeting a mental health outcome.

We had no idea what we were in for.

It turned out to be a huge effort that took the work of nearly 50 people over the next four years to complete. We jokingly called it the “DeathStar Project” because, just like the space station in the Star Wars movies, the project was gigantic, took forever to build, and (we hoped) would have a major impact on how we think of psychotherapy.

54.633 studies were each rated twice to see if the analyses were properly done. Initially, it appeared a bit over 1,000 of these were in the running, but as we kept digging in more fell away (for example, we put aside studies in which one outcome mediated another). To get at the core findings we focused on process measures that were replicated at least once in our database. We ended up with 281 clear findings using 73 different measures. Finally, a couple of weeks ago, the results of one of the largest reviews I’ve ever seen attempted appeared in the well-known journal Behaviour Research and Therapy.

As you might have guessed, there is not just one pathway of change, but many; each supporting people differently in different contexts. The surprising finding, however, is that one single set of skills proved far more commonly effective than anything else. It was more frequently found than self-esteem; support from friends, family, or your therapist; and even whether or not you have negative, dysfunctional thoughts. The most common pathway of change was your psychological flexibility and mindfulness skills. This small set of processes accounted for nearly 45% of everything we know about why therapy works, using the demanding criterion of a successful mediational analysis. When concepts were added that were very similar to psychological flexibility and mindfulness (e.g., self-compassion, behavioral activation, anxiety sensitivity) it soared to nearly 55% of all the successful mediational findings.

The Three Pillars of Psychological Flexibility

We can now say with certainty that psychological flexibility is the single most commonly founded skill of importance to your mental health and emotional well-being. Whether you suffer from anxiety, depression, addiction, or any other kind of mental distress; psychological flexibility helps you deal with these issues more effectively, and move your life in a meaningful direction.

So what does this skill entail? It’s best to think of it as three skills in one.

Pillar #1 Awareness

The first pillar of psychological flexibility is awareness. This means noticing what happens in the present moment: What thoughts show up? Which feelings? And what other sensations can you notice in your body? It also means noticing these things from a more spiritual part of you — your witness or noticing sense of self.

The “now” cannot be experienced with words alone — it needs to be attentively experienced. It’s the difference between talking about the flavor of an orange, and actually tasting the fruit. The latter is much richer than the former. Instead of being “caught up” in your own head, awareness is about being in the here and now. And even more, it entails the ability to deliberately direct, broaden, or focus on different aspects of your experience.

And all of that from the part of you that connects you in consciousness to others.

Pillar #2 Openness

The second pillar of psychological flexibility is openness. This means allowing difficult thoughts and painful feelings — exactly as they are, without them necessarily having to change in any way or form before you can move ahead toward the kind of life you want to live. This part is counterintuitive and often hard to grasp, because people tend to seek therapy precisely to get rid of their negative thoughts and feelings. Unfortunately, the mind does not work this way. Generally, the harder you try to eliminate pain, the more it will control your life. Instead, openness is about dropping the internal fight, allowing thoughts and feelings to be what they are — merely thoughts and feelings — without them needing to control you. Ironically, in that open posture, thoughts and feelings often do change in a more positive direction.


Pillar #3 Valued Engagement


The third and final pillar of psychological flexibility is valued engagement. This means knowing what matters to you, and taking steps in this direction. It involves being in contact with your goals — objectives you want to reach or achieve — and your values — those personal qualities you choose to manifest and be guided by, regardless of a specific outcome. These matters need to be freely chosen, rather than being forced on by others, or mindlessly followed out of custom. But once you have clarity about what matters, you can take action to build sustainable habits that make your life more about what gives it meaning.


Psychological flexibility is the single most important skill for your mental health and emotional well-being. The first two pillars create a working approach to mindfulness skills. In close connection with other processes of change, psychological flexibility and mindfulness are the smallest set of skills that do the most good in the most areas. And we now know a major part of the answer to the question “why does therapy work?”. Very often it works because it establishes greater awareness, openness, and values-based engagement in life.

When you are frustrated at work, you can notice your frustration, allow it to be, and still take steps to complete your assignment. When you are in a fight with your spouse, you can acknowledge the pain, embrace it as a learning opportunity, and build plans to move forward stronger together. Psychological flexibility empowers you to stop fighting yourself, and orient your life in a meaningful direction. It is accessible to you right here and now. And just like any other skill, the more you practice it, the better you will become at it.

The history of science and human development shows that when we have a clear target, we can as a human community learn how to move it. Psychological flexibility and mindfulness are not the only processes of importance in creating mental health but they are the most commonly significant ones.

That gives us all a target for change.