Holistic health assessment has been viewed with proper skepticism by professional psychologists as a result of problems of definition, psychometric adequacy, and legitimate application. This paper provides a definitional perspective that permits distinctions to be made among health assessment domains including health hazard appraisal, health status, holistic health, well-being, and wellness. Psychometrically respectable instruments in all domains are identified and described, and legitimate applications and potential uses for instruments are discussed. Instruments in all health assessment domains have been underutilized.