The study uses data collected by a survey of computer-based medical information system end users in a large hospital in the southeastern United States. The theoretical model examined using this data links several antecedents to the end users’ organizational commitment, mediated by computer self-efficacy and outcome expectancy. These antecedents are past computer experience of the end user, computer staff support for the computer system, ease of system use, and the degree of system use (i.e., percentage of time the system is used by the end user). The empirical results indicate that past computer experience and the degree of system use positively influence the end user’s organizational commitment through both computer self-efficacy and outcome expectancy. These also show that computer staff support and ease of system use positively impact the end user’s organizational commitment through outcome expectancy. From these results, conclusions and implications for practicing managers are discussed.