There are very few psychodiagnostic instruments for assessing the emotional stability, cognitive outlook, and coping style of clients seen in rehabilitation settings. Established clinical tools have been designed for psychiatric populations and are only tangentially relevant. Excellent recent instruments for rehabilitation populations tend to focus on overt behavioral indices or vocational aptitudes. To supplement these latter realms of functioning, the Millon Behavioral Health Inventory (MBHI), a 150-item self-report inventory, may be seen to provide measures relevant to the client's psychological outlook and prognosis. It also appears useful as a guide for treatment planning and psychological counseling. The rationale, development, and uses of the MBHI are briefly described, while the focus of each of the instrument's 20 scales is also outlined.The client with rehabilitation needs may enter the health care system with a physical, functional, and/or psychological problem. Although medically stabilized, at least in regard to life-threatening concerns such as postsurgical complications, the client is now beginning a long, arduous, and highly individualized recovery process. Clinical health psychologists (Millon, Green, & Meagher, in press) play a central role in all phases of this process-from diagnosis, to treatment planning, to direct work with the client in facilitating recovery.The responsibilities of this multifaceted role neither require that the psychologist discard familiar clinical skills or techniques nor transform himself or herself into a totally new professional. However, they do call for the use of assessment and treatment tools that are more relevant to rehabilitation populations than those in the standard clinical armamentarium. The psychologist should seek creatively to extend previously acquired competencies to fit these new responsibilities. One such skill, that of psychodiagnostic assessment in rehabilitation settings, is the focus of this article. Fulfilling the role of psychodiagnostician in this setting may require considerable ingenuity and flexibility, since the task calls for tools, concepts, and strategies other than those that psychologists are likely to have been trained to employ in conventional mental health settings.