Partners Healthcare System, Boston, MA, has developed a patient Web portal that features a patient-controlled electronic "journal" to allow patients to interact with their physician's electronic medical record. Patients can view and respond to health reminders, critique electronic chart information maintained by their doctor's office, enter additional clinical information, and prepare information summaries before an office visit. Creating shared information resources to support a collaborative care model required analysis of the business, architectural, and workflow requirements of the patient-controlled clinical portal and the physician-controlled electronic medical record system. In this paper we describe the challenges in aligning the two systems and serving the different user groups. Coupling the Patient Gateway system, serving over 8700 patients of 90 physicians as of September, 2003, with the Longitudinal Medical Record system, serving over 4000 physicians, has required a clear definition of user goals and workflow, well-defined interfaces, and careful consideration of system assumptions to succeed.