The study examined the distinction between two traditional work absence measures: frequency, reflecting voluntary absence, and duration, reflecting non-voluntary absence. The two measures were compared in a test of the relationship between work absence and employees' perceptions of organizational ethics. Questionnaires and archive data were collected from 1,016 teachers in Israel. Organizational ethics was represented by three variables: ethical climate (caring and formal), organizational justice (distributive and procedural), and teacher's tendency to misbehave. Results showed that four ethical constructs (caring climate, formal climate, tendency to misbehave, and procedural justice) were related to absence frequency, while only one (caring climate) was related to absence duration. The findings add to previous research on the distinction between voluntary and involuntary absence measures, and the superior sensitivity of frequency over duration as a measure of voluntary absence. In practice, the results may encourage principals and managers to create ethical workplaces to minimize absence frequency.