Given that imitative behavior is a social phenomenon, an often put forward claim in the literature is that imitation should be modulated by social factors. Motivational theories explain social modulation with the notion that people use imitation as a tool to affiliate with others. As a result, individuals are expected to imitate others more when they have an affiliation goal. Self-other overlap theories suggest that imitative tendencies are learned responses that develop as a result of self-observation and interaction with other, often similar individuals. As a consequence, imitation is expected to increase if perceived similarity is high. Interestingly, the empirical evidence for these theories has been rather mixed. That is, while there is cumulative evidence for the influence of some social factors, there is only preliminary or no evidence for the influence of other social factors. In this chapter, we review the evidence in favor and against social modulation of imitative behavior, explain why some, but not other factors influence imitation, and then end with outlining potential avenues for future research.