The authors analyze different ways that problem solving groups organize structurally. The argument applies to all groups but because of historical facts, all-male and all-female groups instantiate the situations described. Essentially, groups that organize around recognized (“legitimate”) characteristics are more effective than groups in which organizing principles are unclear or inconsistent. While males usually organize in this way, females often use differing or ambiguous principles, and thus, are less effective. Explicit authorized designation of a leader in all-female groups should remove ambiguity in all-female groups and make their interaction patterns more similar to those in all-male groups. The analysis and predictions were supported by research on discussion groups. Walker and Fennell (1986) refer to this research