OBJECTIVES: To assess the level of user acceptance for an Internet-based methodology for collecting patient outcomes data from an observational multi-site postmarket study gathering data from community based ophthalmic practices. METHODS: The study coordinator at each participating site (N=41) was issued an ID & Password for logging onto the secure and confidential site. Training of the study coordinators on how to use the site and patient confidentiality considerations took about 30 minutes. Two sets of questions were being asked: Physician Questions (8 baseline, 4 followup) and Patient Questions (9 baseline, 18 followup). Patients were followed for approximately six months. A small honorarium in return for completing the study documents was paid. Both glaucoma specific clinical & QOL data was collected and analyzed. RESULTS: Forty-one sites registered 360 patients for the study. Final follow-up data was entered on 318 of the 360 registered patients (88%) using the web-based case report forms. Eighty-seven percent (36/41) responded to a user survey and all respondents 100% (36/36) felt the system was simple and east to use. Several users were so enthusiastic they gave text quotes of additional positive praise on the survey. Many indicated they actually enjoyed participating. CONCLUSIONS: Internet-based post-market studies are a promising methodology for the benefit of both the study sponsor and participating sites.