How Change Happens in Equine-Assisted Interventions gives clinicians and researchers an intervention theory on the mechanisms of change during psychotherapy and other interventions that incorporate horses. Chapters introduce the concept of intervention theory, present a theory of the problem (what the client comes with), theories explaining the intervention (what is done during a session), and theories of change (what happens in the mind of a client), with each theory’s function described. Using an autoethnographic approach, the authors describe, deconstruct, and analyze personal experiences as clients during an equine-assisted intervention. Then the authors present and apply a unique intervention theory by linking it to the thoughts and experiences of clients in and after a session. Practitioners will come away from this book with a unique perspective on the field and with an increased understanding of what their clients are thinking both in and out of session. Researchers will have an explanatory theory from which to draw testable hypotheses when studying interventions incorporating horses.