The authors present an overview of the academic literature on charitable giving based on a literature review of more than 500 articles. They structure their review around the central question of why people donate money to charitable organizations. They identify eight mechanisms as the most important forces that drive charitable giving: (a) awareness of need; (b) solicitation; (c) costs and benefits; (d) altruism; (e) reputation; (f) psychological benefits; (g) values; (h) efficacy. These mechanisms can provide a basic theoretical framework for future research explaining charitable giving.