The primary objective of this article is to see if and how attendance policy influences class attendance in undergraduate-level principles of macroeconomics classes. The second objective, which is related to the first, is to examine whether the nature of the attendance policy matters in terms of its impact on class attendance behavior. The results provide strong support that having an explicit attendance policy reduces absenteeism. The results relating to the nature of the attendance policy point to the greater effectiveness of a policy that punishes students for missing class rather than one that rewards students for good attendance. (Contains 4 tables and 3 notes.)