Student affect--the attitudes, interests, and values that students exhibit and acquire in school--can play a profoundly important role in students' postschool lives, possibly an even more significant role than that played by students' cognitive achievements. If student affect is so crucial, then why don't teachers assess it? One deterrent is that few teachers know how to do it. Yet assessing affect is relatively straightforward. Affect inventories are typically patterned after the attitudinal inventories that organizational psychologist Rensis Likert devised almost 80 years ago. An inventory presents a series of statements with which students are asked to agree or disagree. To score the inventory, points are awarded for "agreement with positive statements" as well as for "disagreement with negative statements." For important affective outcomes teachers wish to promote in their schools--for example, students' sense of social responsibility--the time has come to do more than merely talk about these desirable outcomes. It's time to measure them.