Health Information Technology (IT) implementation can fail or meet high levels of user resistance for a variety of reasons, including lack of attention to users' needs and the significant workflow changes induced and required by the technology. End-user satisfaction is a critical factor in health IT implementation. In this paper we describe the process of developing and testing a questionnaire to evaluate health IT implementation, in particular Computerized Provider Order Entry (CPOE) and Electronic Health Record (EHR) technologies. Results showed evidence for the validity and reliability of the questionnaire. The Systems Engineering Initiative for Patient Safety (SEIPS) questionnaire is relatively easy to administer and allows researchers to evaluate different aspects of health IT implementation. Results of this research can be used for benchmarking results of future studies evaluating health IT implementation.