The purpose of the present study was two-fold. The first was to examine further the prevalence of headache in a college sample. The second was to evaluate the test/re-test reliability of the questionnaire measure of prevalence and its concurrent validity (by comparing information collected on it to like measures collected by systematic, daily headache diary records). Headache was found to be a widespread phenomenon that was affecting at least 45% of all students once per week, and 35–45% of the students experienced headache severe enough to disrupt planned activities. Headaches experienced by females tended to be more frequent, more intense, and of longer duration. Individual questionnaire items overall evidenced high test/re-test reliability over 1, 4, and 8 weeks, although responses to inquiries about location and nature of headache pain were varied. However, questionnaire estimates of frequency, duration, and intensity showed little correspondence to data obtained from diary records. In general, questionnaire measures appear to underestimate frequency and duration, while overestimating intensity, when compared to actual recordings of headache activity. Thus, when used in isolation, global questionnaire measures of headache do not appear to provide accurate information about the occurrence of the problem.