The AIDS Clinical Study Group (CSG) is a multi-disciplinary research effort that will 1) accumulate an immense amount of data and 2) share this data between different inter- and intra- institutional projects. We propose to establish a data management and analysis group that will provide both the personnel and sophisticated computerized tools to permit the maximum utilization of the data collected. The enrollment of patients into four cohorts that will be tracked for up to five years requires a central database that is accessible to all other projects that recruits patients from these cohorts. We propose to utilize the General Clinical Research Center (GCRC) computer facility by expanding existing hardware to allow increased users without degradation of response time. By using this existing computer facility, the CSG will have access to CLINFO, BMDP, MAIL and BBOARD. Personnel will perform data administration, database management, data entry, statistical review and consultations, and statistical programming.