This article examines traditional and modern psychological characterizations of religiousness and spirituality. Three ways in which religiousness and spirituality are polarized by contemporary theorists are examined: organized religion versus personal spirituality; substantive religion versus functional spirituality; and negative religiousness versus positive spirituality. An alternative approach to understanding religiousness and spirituality is presented that integrates rather than polarizes these constructs, and sets boundaries to the discipline while acknowledging the diversity of religious and spiritual expressions. Directions for future investigations of these two constructs are presented.Psychological investigations of religiousness and spirituality date back to the turn of the century (Coe, 1900;James, 1902James, /1961Starbuck, 1899). From these pioneering efforts to the present, a number of theories have been developed, many empirical studies have been conducted, and considerable knowledge about religious and spiritual belief, experience, and behavior has been accumulated. With the approach of the new millennium, popular and scientific interest in religion and spirituality continues