The term “psychologically informed health care” refers to the comprehensive integration of psychological principles into health care. Psychologically informed health care has the potential to lead to a transformation of care, resulting in truly transdisciplinary care. To facilitate its future development, we discuss key characteristics of this approach. These include the direct mode (psychologists assessing and treating patients themselves) and indirect mode (psychologists working through other health care providers) of integrating psychological principles into healthcare; the range of health domains targeted using this approach; transdisciplinary care, transcending traditional disciplinary boundaries; and the positioning of care. We describe a framework for transdisciplinary care, which we refer to as the Framework for Catalytic Collaboration. This framework comprises six dimensions: setting, disciplines, patients/clients, mode of psychological care, primary components of care, and primary targets of care. We also provide four brief illustrations of psychologically informed health care. Finally, we discuss future directions, including the need for professional recognition of the indirect mode, financing of the indirect mode, cross-disciplinary training and trans-disciplinary research.