Psychotherapy is an immensely diverse field of practice, in which multiple models and protocols coexist. This diversity can be an asset but can sometimes hinder the path toward a common understanding of what works in psychotherapy. The aim of this article is to show that the therapeutic alliance construct can provide an integrative frame of reference when it comes to understanding the psychotherapeutic process.

This narrative review of the therapeutic alliance concept embraces the diversity of theories and practices in psychotherapy. We draw on the contextual model (Wampold, 2001) and the therapeutic alliance model (Bordin, 1979).

The reviewed studies mainly focus on individual psychotherapy for adult patients and are drawn from international literature from the past fifty years.

We explore the epistemological and practical implications of these studies. One part of the research explores the links between alliance and psychotherapy outcomes, while another explores alliance as a therapeutic process.

The contextual approach and the alliance model can be used to provide a definition of psychotherapy that is common to different schools of thought. These concepts offer a framework for quality psychological care.