Equine facilitated psychotherapy (EFP), a new field in psychology, is an alternative method of therapy that uses horses to facilitate therapeutic outcomes. There is minimal peer reviewed literature and few published studies examining efficacy. The conceptual lens of this study was grounded theory, as there is insufficient evidence of theoretical frame-works guiding equine assisted therapy. The purpose of this exploratory concurrent mixed methods study was to examine the theoretical foundation of practitioners; program make up; client populations; efficacy of program; and why the horse serves as the therapeutic catalyst of this model. A 43-item survey was sent to 800 programs, current members of the North American Riding for the Handicapped Association, Equine Assisted Learning and Growth Association, and the Equine Facilitated Mental Health Association who use equine assisted therapy. Twenty nine percent (n=232) of the surveys were returned. Chi square and cross tabulations were utilized to examine relationships between specific theoretical orientations of therapists and the therapeutic role served by the horses. Results illustrated that therapists who used experiential theory were more likely to use horses for development of confidence, development of self-efficacy, mirroring of behavior, and manner in which the therapist treats the horse. Open coding of qualitative questions was followed by axial coding into emergent themes were used to confirm and expand the quantitative results. Results illustrated the primary orientation within EFP was experiential theory; and that horses were universally considered essential aspects of the program because specific characteristics of the species facilitate key therapeutic processes. This study contributes to social change by providing the EFP field with a comprehensive analysis of current conceptual orientations and practice that can inform efforts to unify and extend this emerging therapy.