""""""""This is an application to become a participating Clinical Center in the Ocular Hypertension Treatment Study (OHTS). The complete details of the OHTS rationale, design and methods are contained in the OHTS Manual of Procedures. This proposal provides the necessary documentation of the abilities for the Washington University Eye Center and its staff to screen ocular hypertension patients and achieve a target of 50 eligible patients who will be enrolled over a 24 month period: In summary we anticipate the 50 patients will come from the following sources: 1) 43 eligible patients from the Ocular Hypertension Risk Study conducted at the Washington University Eye Center from 1981-1992 2) 23 eligible patients from the Long Term Timolol Study conducted at the Washington University Eye Center from 1979-1988. 3) 8 patients who are OHTS eligible and who have agreed to participation, from a 2 month prospective screening in the Glaucoma Service at the Washington University Eye Center 4) Prospective screening of an additional 140 ocular hypertensive patients in the Glaucoma Service at the Washington University Eye Center 5) Recruitment of patients from the St. Louis area utilizing the private practice resources of community based ophthalmologists. 6) Prospective screening of ocular hypertension patients from the Barnes Hospital Eye Clinic""""""""