The intent of this application is to document the ability of Wills Eye Hospital's Glaucoma Service to participate as an effective and productive clinical center in the proposed multicenter clinical trial, entitled "Collaborative Initial Glaucoma Treatment Study" (CIGTS). This study's purpose is to evaluate whether initial treatment of open angle glaucoma is more effective by means of a stepped, medical regimen or by means of a surgical approach. The Wills Eye Hospital (WEH) Clinical Center will participate in the CIGTS by identifying and recruiting eligible patients, administering the treatment regimen as assigned by the CIGTS's Coordinating Center and defined within the study's Manual of Operations, following and retaining study patients, recording and transferring study data to the Coordinating Center, and contributing to reports that will present the CIGTS results. This application describes the ability of the Wills Eye Hospital's Glaucoma Service Clinical Center to enroll approximately 32 patients per year, based upon pilot studies of patient eligibility conducted during a three month period. Details are provided of our plans to identify, recruit, follow, and retain these patients, our intent to obtain consistently high quality data on the visual outcomes of treatment, and the personnel and facilities available within our center to carry out the provision of the CIGTS's Manual of Operations.