Despite the differences in the two judicial systems, both courts operate in the same context and use lawyers and judges who trained together at law school, have a common legal history, and share the same social, political, and economic preconceptions. Judicial cooperation should focus on issues involving joint Federal-State jurisdiction, potential changes in jurisdiction, working out systems to avoid scheduling conflicts in Federal and State cases involving the same attorneys, and sharing pro bono services by attorneys. Additional areas where coordination would be desirable would be sharing computerized records to reduce administrative difficulties, adopting a single system for bar membership and discipline, improving jury selection procedures, and using one data base from which to draw both Federal and State jurors. In the criminal justice area, cooperation between the State and Federal judicial systems should entail using Federal facilities such as old Conservation Corps camps to reduce prison overcrowding, joint sentencing by State and Federal judges in certain cases, and cooperation between probation services. Although the legislature bears the main responsibility for better coordination of the State and Federal judicial systems, judges can encourage cooperation through joint training sessions and the State-Federal Judicial Council. Footnotes are provided.