Open and distance learning (ODL) gives learners control of the time, place, and pace of learning, often being characterized as flexible learning. However, this flexibility goes hand-in-hand with procrastination and non-completion. As a result, the efficiency of the educational process is of importance to ODL providers, government funding agencies, and learners themselves. Despite its importance, measuring efficiency in ODL is problematic. This article presents a case study in measuring educational efficiency using a method which reflects the special characteristics of ODL. The article concludes with a discussion of the wider applicability of the measurement method in the context of lifelong learning. (Contains 3 tables, 3 figures and 2 notes.)