We present an analysis of moral motives underlying economic and social decision making. The underlying idea is that moral motives are psychological instruments that induce people to cooperate in pursuit of collective goals and to suppress destructive competition. Different social contexts are associated with different collective action problems, which call for different cooperative relationships. These different cooperative relationships are associated with different moral motives. Cooperative contexts, associated with positive externalities, call for moral motives that reward people for promoting the common good, thereby enabling them to internalize the positive externalities. Competitive contexts, associated with negative externalities, call for moral motives that discourage people from harming one another, thereby promoting the internalization of the negative externalities. In this framework of analysis, people are subject to multiple, context-dependent moral motives. The diverse moral principles underlying the diverse moral motives are to be understood not as mutually exclusive alternatives, but as components to be applied in combination with one another.