This study reports early results of a project that addresses the process of computerizing medical records in multiple ambulatory care sites of a health system. The study focuses on end-user attitudes before, during, and after implementation, through the use of questionnaires, interviews, and participant observation. Knowledge about end-user attitudes prior to computerization may contribute to planning for the training and implementation process. Tailoring these processes to meet the varying needs of user groups may result in a higher level of functional use of the system and less stress to the persons involved in its use. One implementation plan may not work for all sites when there are differences in size of the clinic, work flow patterns prior to implementation, and computer experience among personnel. Preliminary analysis of post-installation questionnaires and interviews six months after the installation point to a number of areas that might be usefully addressed in future installation efforts.