We seek to explain the structure of leadership, power, influence, control (they are equivalent terms) over community decisions. In its most general aspect, we conceive of control over decisions within a democratic context as the result of low but (as among people) highly disparate amounts of interest in public affairs; the high costs and comparatively low returns from activity in public affairs; the unequal but dispersed distribution of resources; and the independent, conflicting relationships among leaders. Interest, activity, and access to effective resources are separately viewed as necessary and together as sufficient conditions of leadership. Conflicts among leaders supply the dynamics of the system. These variables, the factors affecting them, and their inter-relationships, form the basis of our discussion.1