Section 1983 of the Civil Rights Acts of 1871 and 1970 served as the main vehicle of court intervention in prisoner grievances. Through court challenges, inmates have obtained decisions recognizing greater access to courts and legal counsel, greater religious freedom, freer expression and access to the media, more liberal correspondence and visiting rules, a right to medical treatment, limited rights to organize, protection of their personal safety and lives, and protection from cruel and unusual punishment. This last protection has had wide ramifications for both confined adults and juveniles. In an effort to curb inhumane treatment within prison systems, the courts have ordered prison closings, restriction of inmate population, and, in one case, the placement of a State system in 'receivership' under a State governor. Enforcement of court orders has, however, been slow and viewed as ineffective by many prisoner rights advocates. Standards for operation of correctional facilities have been linked to court decisions, and correctional practices directly relating to case law are designed to protect the constitutional rights of confined offenders. Yet standards and court decisions are only the initial impetus to possible change, requiring also the compliance and implementation of corrections administrators. Extensive case examples are cited, and a chart shows major prisoner rights in the U.S. by State, case citation, system or unit affected, and major issues challenged. Ninety-eight references are provided.(Author abstract modified)