An integrative model of the conative process, which has important ramifications for psychological need satisfaction and hence for individuals' well-being, is presented. The self-concordance of goals (i.e., their consistency with the person's developing interests and core values) plays a dual role in the model. First, those pursuing self-concordant goals put more sustained effort into achieving those goals and thus are more likely to attain them. Second, those who attain self-concordant goals reap greater well-being benefits from their attainment. Attainment-to-well-being effects are mediated by need satisfaction, i.e., daily activity-based experiences of autonomy, competence, and relatedness that accumulate during the period of striving. The model is shown to provide a satisfactory fit to 3 longitudinal data sets and to be independent of the effects of self-efficacy, implementation intentions, avoidance framing, and life skills.