AbstractThis paper describes how the analytic hierarchy process was applied to a decision concerning the selection of a computer operating system. Various practical issues and problems which arose whilst using the process are discussed. The method was found to be a useful aid for identifying the criteria upon which a decision depends. It also revealed useful data about the concerns and preferences of decision-makers. Some problems were, however, encountered when assessing the importance of an intangible factor relative to a tangible factor. Also, it was difficult to interpret the options' final scores because the method does not provide an indication of statistical significance.