This paper is one of the first to examine a potentially important yet ignored area of information technology usage research, namely IT adaptation. Integrating adaptive structuration theory with findings from prior IT usage research, we propose a theoretical model of IT adaptation that elaborates the causative drivers, effects, and underlying dynamics of the adaptation process. A longitudinal study is proposed to empirically test the hypothesized model. We present results from a pretest study that validated our choice of constructs and generated initial measurement items for new constructs, and expect to complete and present instrument validation, data collection, and statistical analysis at the conference. Potential contributions of this study for IT usage research and practice are discussed.