Abstract
A "predisposition/opportunity" model is developed of the relationship between individual motives to contribute resources to organizations & organizational incentives to induce commitments. Social motivations involve three analytically-distinct components: rational choice, normative conformity, & affective bonding processes. Each by itself is incomplete as an explanation for individual decisions to contribute personal resources to the collectivity, but together the three motivations form a synthesized model. Corresponding to these motives, organizations may offer three types of incentives: utilitarian, normative, & affective. Combinations of these inducements lead to an eight-fold typology of incentive systems involving pure & mixed types. The implications of this predisposition/opportunity model are drawn out in a series of research hypotheses. 1 Table. HA.