Sharing of knowledge takes place mainly in social networks. Anthropological methods can help to identify networks where exchange on certain topics takes place. Once transparency about existing networks has been established, they can be fostered cautiously. Conditions for successful knowledge sharing are examined. Where people are in close contact and relationships are multiplex, knowledge sharing works best. Likewise, an anthropological theory of exchange confirms a focus on networks. An example of successful knowledge sharing in practice demonstrates important factors: Direct, oral exchange of knowledge is intrinsically motivating. People sharing knowledge orally can make their name among their peers and get immediate feedback from them. Therefore, a personalized approach is recommended where the supplier of knowledge provides advice following individual requests. KM systems should mainly establish transparency about relevant carriers of knowledge.