Knowledge management systems (KMS) are an important component of implementing successful knowledge management initiatives in organizations. In order for such systems to achieve their intended benefit, it is important that the knowledge workers both contribute knowledge to the systems, and that they reuse knowledge which has been contributed by others. It has previously been shown that there is often reluctance on the part of employees to participate in both of these activities. This study explores the effect of the usefulness of a knowledge management system and incentives on intention to contribute and reuse knowledge, controlling for tolerance of ambiguity. The results of a pilot laboratory study measuring the effects of usefulness and incentives on intention to contribute and reuse knowledge are presented in this paper.