In the previous chapter, we discussed how the presence of other people can affect a person’s performance. The majority of this research was concerned with how the social environment or group influences individual people. However, in most instances there is more to group influence than simply other people’s presence. For example, on many occasions, we work together as part of a group—whether it be completing a proposal for a supervisor or instructor, planning a social event such as a party or wedding, or playing together on an office or intramural softball team. Typically, when working in such groups, members perceive themselves to be part of some larger collective in which they attempt to accomplish a shared objective and in which they share a common fate. In this chapter, we focus on people’s performances when working as part of a group and on the social motivation losses that can sometimes result. Research on how people function when working together as part of a group has raised several intriguing questions: What are the variables and processes that produce social motivation losses? What are the characteristics of group members and of the social environment that produce such losses? And finally, if social motivation losses can occur when working in groups, then how can they be reduced or eliminated? We discuss some answers to these questions for a variety of distinct types of social motivation losses. Underlying our discussion is attention to the nature of the type of task performed by the group. Finally, we end this chapter by discussing some integrative models of social performance, which build on the theories of social facilitation (Chapter 5) and those of this chapter.