Knowledge management strives for effective capture and application of organizational knowledge, a resource imperative in sustaining organizations. To better achieve knowledge management initiatives, examination of factors influencing adoption and usage of knowledge management systems (KMS) are of great interest. Implementation of technological solutions considered organizational innovation is subject to potential problems of resistance, implying analysis of social factors equally important to technological factors. With Innovation Diffusion, Theory as a foundation, this research examines factors influencing adoption and usage of KMS. The model is extended to include Reciprocity Expectation, an important factor affecting knowledge management processes. Results indicate that some factors are important in determining adoption while others are important for continued usage. This research emphasizes careful consideration and re-evaluation of both social and technological factors throughout all stages of technology implementation; more specifically, Reciprocity Expectation may be an important factor affecting length of adoption, but insignificant in determining continued usage.