As a current and popular instructional technology, Personal Response Systems (PRS, or "clickers") are seen by many educators as a path to increased learner-instructor interactivity (especially in large-class settings) that produces learning outcomes superior to those achieved in technology-lean classrooms. While this expectation may appear reasonable at first consideration, the result is certainly not a "given." This article describes some current uses of the PRS technology, relates those uses to student expectations, and raises implementation and course-planning issues.