Certain managerial functions are necessary or of greater importance in certain organizations. The following relations between organization types and leadership roles are hypothesized: expert organizations and producers, bureaucratic organizations and administrators, group organizations and integrators, and task organizations and entrepreneurs. The analysis shows that striving for results and achieving goals (i.e. producer role) is a role requirement that appears in all types of organization, whereas integrating behavior was required as a secondary requirement, again in all four types of organization. It was also found that the union stewards overestimated their leaders' efficacy as administrators and entrepreneurs, whereas the leaders themselves overestimated their own efficacy as producers and integrators. The leader's length of service with the organization reduces the inclination towards the producer role, but is conducive to the role of administrator.