Patients dying before 1989 were identified using the VA's Beneficiary Identification Records Location Subsystem and the National Death Index (NDI). Using NDI information to locate them, death certificates were obtained on all dead patients. Arrangements were made to collect data on the VA hospitalizations occurring after antihypertensive treatment had begun, and application was made to match patients against the USRDS Dialysis and Transplant Registry. The basic clinical data were collected in 32 VA Hypertension Screening and Treatment Program (HSTP) clinics during the 40 month period beginning in 1974. Approximately 30,000 completed Screening and Evaluation Forms and 75,000 Treatment Visit Forms were completed during the 40 months of data collection. The collected information was entered into the HSTP Master File at the VA Computer Center in Austin, Texas. Predictors were sought for (1) all-cause mortality, (2) cause-specific mortality (obtained from death certificates and hospitalization and clinic records), (3) endstage renal disease (obtained from the USRDS Dialysis and Transplant Registry), (4) VA hospital usage combined with other data related to cost care.