[영문]Recent research suggests that program participants have limited knowledge of the rules governing social programs. These knowledge gaps limit program effectiveness. This article uses a unique survey of Wisconsin welfare participants to explore factors associated with whether single mothers have accurate knowledge of child support rules. It also assesses the accuracy of knowledge gained from their own experience, formal sources, and informal sources. Multivariate analyses document the difficulty participants have in understanding new rules. They also highlight the roles that formal sources and clients’ own experience play in obtaining accurate program information. Results suggest the possibility that informal sources provide inaccurate information.