Since the classic leadership studies of Lewin, there has been an effort to identify the contingency variables that may moderate the effects of participation in decision making (PDM) on task satisfaction and performance. In this study, the effects of democratic and autocratic management regimes were examined in laboratory organizations in which groups or departments had either cooperative or competitive orientations toward each other This allows the examination of possible moderating effects of intergroup competition and cooperation on tasksatisfaction andperformance. As expected, people reported more total control or influence, less hierarchization of influence, and more task satisfaction, as a consequence of the greaterPDM, in the democratic than in the autocratic condition. Cooperative-compared with competitive-intergroup relations produced higher task satisfaction and better task performance. As expected, intergroup competition resulted in more mutual hostility and rivalry than cooperative relations, particularly in democratic groups in which the members had more opportunities to interact with each other than in autocratic groups. Group members attributed more total influence in the competitive condition, in which they had to cope with a more complex, threatening task environment than in the cooperative condition, in which they were faced with a more benign environment. All in all, it appears that intergroup competition and cooperation within organizations might be another important contingency variable that mediates the effect of PDM on task performance and satisfaction.