To advance research and inform practice, the authors developed an observational rating system of client behavior reflecting strong and weak therapeutic alliances in couple and family therapy. The System for Observing Family Therapy Alliances (SOFTA), in both English and Spanish, has 2 dimensions that are common across therapy modalities ("emotional connection to the therapist" and "engagement in the therapeutic process") and 2 dimensions that reflect the uniqueness of conjoint treatment ("safety within the therapeutic system" and "shared sense of purpose within the family"). Psychometric support is provided by 5 reliability studies, an exploratory factor analysis with data from 120 diverse English- and Spanish-speaking couples and families, and meaningful associations with various process and outcome indices. Recommendations are made for using the SOFTA in research, training, and (self-)supervision.