Motivating users of a knowledge management system to contribute their knowledge to the system is critical for the success of the overall KM initiative [31]. In this pa- per, we will argue that it is possible to map the knowledge- sharing problem to a public-good game and that voluntary contribution to a public good is inefficient. One possible solution to this dilemma lies in changing the payoff ma- trix for participants through incentives for knowledge shar- ing. However, this solution needs to be seen against the light of motivational crowding-out theory, which suggests that monetary incentives may undermine intrinsic motiva- tion and thus affect the total impact of incentives negatively [21, 20, 40]. This thesis is particularly relevant because ex- perimental studies of generic public-good games indicate the existence of intrinsic motivation: In one-round public good experiments, the cooperation rate observed was sig- nificantly higher than self-interest alone could explain [35]. Another very important finding of public-good games con- cernstheroleofculture: experimentalstudieshaverevealed huge differences in the degree of cooperation among differ- ent cultures