A cooperative organizational climate is often argued to promote knowledge-sharing behaviors among employees. However, research indicates that managerial interventions aimed at shaping the organizational climate can be difficult to execute. We develop and test a contingency model of intrinsic motivation and job autonomy as moderators of this relationship. We find that the social climate for cooperation better predicts knowledge sharing when employees show low levels of intrinsic motivation and have high levels of job autonomy. This suggests that a cooperative climate and intrinsic motivation are substitutes with respect to their impact on knowledge-sharing behaviors, while climate and job autonomy are complements. We find support for these ideas in data gathered from a sample of 170 employees of a knowledge-intensive firm.