The purpose of the authors' study was to understand the reasons why students comply with requests instructors make and compare these reasons with instructors' perceptions of why students comply. Students and faculty at two universities completed the Interpersonal Power Inventory to assess reasons for compliance. Students were more likely to comply with requests for "soft power" reasons, such as understanding the instructor's rationale behind the request or respect. Students were less likely to report complying with requests for "harsh power" reasons, such as wanting a high grade or avoiding punishment. Instructors were fairly accurate in perceiving students' reasons for compliance, but they underestimated students' likelihood of compliance. (Contains 5 tables.)