I review a burgeoning program of research examining people’s perceptions of their influence over others. This research demonstrates that people are overly pessimistic about their ability to get others to comply with their requests. Participants in our studies have asked more than 14,000 strangers a variety of requests. We find that participants underestimate the likelihood that the people they approach will comply with their requests. This error is robust (it persists across various samples and requests) and substantial (on average, requesters underestimate compliance by 48%). We find that this error results from requesters’ failure to appreciate the awkwardness of saying “no” to a request. In addition to reviewing evidence for the underestimation-of-compliance effect and its underlying mechanism, I discuss some factors that have been found to strengthen, attenuate, and reverse the effect. This research offers a starting point for examining a neglected perspective in influence research: the psychological perspective of the influence source.