What works In Psychotherapy? Factors That Make a Difference, Trust, and Success

Since the 1970s, researchers have been investigating two questions: Does psychotherapy actually help, and how does it work when it does help? The answer to the “whether” is clear-cut. The question of “how” is more complicated.

Lambert's model of effective factors shows: 40% of therapeutic success is attributable to extratherapeutic factors (living conditions, social environment, client resources), 30% to general factors (primarily the therapeutic relationship, hope, and placebo effects), 20% to therapist effects (individual differences in the effectiveness of individual therapists, i.e., personality, experience, and flexibility), and only 10% to specific techniques of the respective therapeutic method.

The message for anyone wondering what works in psychotherapy: Life outside of therapy and the quality of the therapeutic relationship have a significantly greater impact than the chosen method. And some therapists are simply more effective than others, regardless of the approach they use.

At first glance, this breakdown seems plausible. Upon closer inspection, however, a fundamental dilemma becomes apparent: Positive life events that result directly from the therapeutic process should actually be attributed to therapy-generated factors. If someone gains self-esteem through psychotherapy and consequently ends a toxic relationship, it is difficult to draw a clear causal distinction. What is the effect of therapy, and what is a life event?

The therapeutic alliance describes the quality of the collaboration between you and your therapist. Can you agree on shared goals? Is trust developing? Do you feel understood, even when you bring up difficult topics?

So far, the the most comprehensive analysis on this topic includes over 30,000 patients from 295 studies. It shows a clear correlation between the therapeutic alliance and treatment success. When the therapeutic alliance is strong, people benefit more from therapy. This doesn’t mean much for any single case. But a patient who engages actively and continues to reflect on the material between sessions gets more out of it on average.

When tensions arise and are then discussed openly, That actually improves the results. It’s okay if things get a little rocky sometimes. What matters is that both sides are willing to talk about it. In the therapeutic relationship, old patterns often come to light—such as the fear of rejection or the desire to please everyone. When such patterns emerge directly during the session and can be discussed, it opens up the possibility of understanding and changing them.

In my experience, this highlights a fundamental truth: Psychotherapy is not a technique that is applied to people. It is a human encounter in which understanding and trust must grow. When this happens, a space is created in which change becomes possible.

Research distinguishes between Insight, emotional processing and new experiences. In practice, these are not separate processes. When someone speaks out for the first time about something that has been hidden for years, and in doing so feels that they are not being judged, then it’s all happening at once: insight, emotion, and a new experience.

I call that Empathetic Understanding. It's not enough to understand it intellectually: Ah, so that's where I get it from—my mom. We need to understand this within our bodies, to sense the connections between the past and the present. Often, there are old conflicts underlying this that were never fully resolved. Sometimes this means truly allowing certain feelings to surface for the first time—grief that was never properly mourned, anger that was never allowed to be expressed. Sometimes it means no longer having to ignore, soothe, or numb a certain part of the body. No longer counteracting it through perfectionism, excessive control, medication, or excessive exercise.

Not necessarily their work experience or academic credentials. Interpersonal skills are more important: Empathy, a psychotherapist’s ability to adapt to a wide variety of people, and a willingness to question one’s own approach. A skilled therapist can tell when therapy is stalling and addresses the issue rather than letting it continue.

Reflecting on one's own work is not a sign of insecurity. It is a prerequisite for providing good treatment. In my experience, therapists who believe they have no blind spots are the most risky.

If you believe that therapy will help you, it actually increases your chances of success. The Research on Expectations of Outcomes shows that patients who begin treatment with confidence benefit more. Conversely, this does not mean that doubts prevent success. Doubts are a natural part of the process. What matters is whether you can even imagine getting better.

It shows how important it is that the treatment makes sense to you personally. The person treating you should be able to explain clearly from the start why the chosen approach could help with your condition. A convincing explanation fosters hope. And hope, in turn, strengthens your motivation to take even difficult steps.

In my experience, hope isn't just about optimism. Above all, it shows itself in a person's willingness to commit to the process, even if it feels uncomfortable at first. Hope isn't a naive expectation that everything will get better quickly. It is the confidence that the journey is worth it.

If you want to embrace deeper changes, it takes time. Long-term therapies can bring about structural changes in personality, but not in just a few sessions. Some internal patterns have developed over years or decades. Understanding and changing them requires patience and perseverance. This has implications for the duration and cost of the process, and both of these factors should be openly discussed from the very beginning.

Experts have been debating this question for decades: Is it the specific techniques that make a therapeutic process effective? Or is it general factors such as the therapeutic relationship, empathy, and hope?

A comprehensive Analysis by Gómez Penedo and Flückiger (2025) examined 43 meta-analyses comprising a total of 1,637 effect sizes from 859 individual studies. The finding: relationship and empathy, as well as therapist-related factors such as competence and adaptability, show stronger associations with therapeutic outcomes than purely technical processes.

That doesn't mean that techniques aren't important. Certain methods, such as EMDR in Trauma Therapy, have been shown to have an independent effect, namely significantly more effective than, for example, cognitive behavioral therapy. But they are most effective when implemented as part of a sustainable working partnership and when they are tailored to individual needs.

Many researchers today advocate for a "both-and" approach: Good psychotherapy requires evidence-based techniques and a strong therapeutic relationship, as well as the ability to adapt both flexibly to the individual. Therapy should not be a rigid program, but rather a dynamic process of support. 

Not a single active ingredient So far, it has met all the strict scientific criteria for a causal mechanism. Research can show that the therapeutic alliance and treatment outcomes are correlated, but it cannot yet conclusively prove that the therapeutic alliance is the cause of the improvement.

Cuijpers and colleagues put it this way: To date, there is no conclusive evidence of causality for either general or specific factors. The effectiveness of psychotherapy is well supported by empirical evidence. What exactly brings about change, however, is much less clear.

Psychotherapy research (internationally known as “psychotherapy research”) has made enormous strides in recent decades. But it is far from over. One thing is clear: Anyone seeking professional help has good reason to be confident.

Read here to find out if a Psychotherapy, including online sessions can take place, or Whether ChatGPT Can Replace Psychotherapists.