An entrepreneur’s prior knowledge and experience play a critical role in his ability to identify and exploit entrepreneurial opportunities. Although entrepreneurship research has acknowledged the role that prior information and prior knowledge play in opportunity recognition, few studies have explored their role in entrepreneurial discovery. The authors test the role of a particular prior knowledge in entrepreneurial discovery within a laboratory setting. Participants were randomly assigned to one of two treatment groups. Those in the propitious treatment were given prior knowledge that oriented them toward the arbitrage opportunity within the experiment, and those in the unpropitious treatment were given prior knowledge that oriented them away. As hypothesized, those in the propitious treatment were significantly more likely to discover the arbitrage opportunity.