Abstract. We present a case study that tracks usability problems predicted with six usability evaluation methods (claims analysis, cognitive walkthrough, GOMS, heuristic evaluation, user action notation, and simply reading the specification) through a development process. We assess the method's predictive power by comparing the predictions to the results of user tests. We assess the method's persuasive power by seeing how many problems led to changes in the implemented code. We assess design-change effectiveness by user testing the resulting new versions of the system. We concludethatpredictivemethodsarenot as effective as the HCI field would like and discuss directions for future research.