Over 99 percent of business schools use student evaluation of instruction to measure teaching and classroom performance. The resultant measures are utilized in judgments of merit pay, tenure, and promotion. In such an environment, an inspection of exceptions to their assumed validity is justified. This paper investigates one such issue that is rarely reported. Simply put: to what extent are students telling us the truth when they evaluate instruction? A literature review indicates that students (1) ignore or falsify answers in light of variables considered more important, (2) give subjective impressions in response to objective questions, and (3) at times give purposefully misleading and false responses. A survey of students found that a majority knew of respondents who had falsified evaluations and that an estimated 30 percent of evaluations contain answers the students knew were not true. In light of these findings, the validity of student evaluation of teaching to improve individual instructor performance, modify curriculum, and create comparative scales to evaluate faculty is called into question. (Contains 1 table and 1 figure.)