The study was done at the Administrative Office of the U.S. Courts and the Federal Judicial Center from June through August 1986. Assessment of the need for additional judges, which is conducted biennially, begins when the Judicial Conference, the policymaking body of the judiciary, requests each court to provide data on the number of additional judges needed. The survey results and information on the courts' caseload supplied by the Administrative Office are reviewed by the Judicial Conference to determine the number of additional judgeships needed. The filings in each court for 1 year is the caseload information used in the assessment process. The filings are weighted according to differences in the amount of time judges spend on various case types. The 1-year weighted caseload is divided by the number of judges authorized for the district. If the calculation shows that the average caseload exceeds 400 cases per judge, the district may need additional judges, providing other factors indicate such a need. Among other factors considered are the court's pending caseload and unusual logistical problems within the district, such as a large geographical area requiring comparatively more travel time. Appendixes provide detailed information on the assessment process used for determining judges needed for U.S. courts of appeals and bankruptcy courts. 3 tables and 1 figure.