The interpersonal tradition (Horowitz & Strack, 2011) provides a rich conceptual and methodological framework for theory-driven research on mechanisms linking religiousness and spirituality (R/S) with health and well-being. In three studies, we illustrate this approach to R/S. In Studies 1 and 2, undergraduates completed various self-report measures of R/S, interpersonal style, and other aspects of interpersonal functioning. In Study 3, a community sample completed a wide variety of R/S measures and a measure of interpersonal style. Many, but not all, aspects of religiousness (e.g., overall religiousness, intrinsic religiousness) were associated with a warm interpersonal style, and most aspects and measures of spirituality were associated with a warm and somewhat dominant style. Spirituality and related constructs (i.e., gratitude, compassion) were associated with interpersonal goals that emphasize positive relationships with others, and with beneficial interpersonal outcomes (i.e., higher social support, less loneliness, and less conflict). However, some aspects of R/S (e.g., extrinsic religiousness, belief in a punishing God) were associated with a hostile interpersonal style. R/S have interpersonal correlates that may enhance or undermine health and emotional adjustment. This interpersonal perspective could help clarify why some aspects of religiousness and spirituality are beneficial and others are not.