Thirty years ago, leaders in psychiatry expressed hope for more interdisciplinary collaboration with family therapy. Since then marriage and family therapy (MFT) has entered the mainstream of clinical practice in psychiatry and psychology. It is mandated for training in psychiatry and psychology. We propose a model for collaboration, training, and treatment in interdisciplinary mental health settings that strives to integrate empirical bodies of knowledge in MFT, psychiatry, and psychology and to provide a usable and testable clinical approach to treatment. It can be taught to trainees with various or limited training in MFT. This model delineates nine critical domains that guide treatment. Flexibility is central to this model, focusing on techniques and clinical methods based on empirically supported treatments, when available, and best-practice standards.