During the last two decades, there has been a great increase in the use of litigation by social reform groups. This activity has been stimulated by the hospitality of the courts to the demands of social reform groups and the availability of subsidized young, activist lawyers. The paper examines the uses of the legal system by social reform groups and the problems that groups have in enforcing changes in legal rules. Three types of litigation strategy are discussed: (1) defensive, where the group, its leaders, or its members are being prosecuted; (2) subsidiary, where litigation is used in aid of other strategies; and (3) affirmative, to accomplish the primary objectives of the group. Most problems occur in implementing affirmative litigation. Four types of enforcement problems are analyzed: (1) Enforcement involves massive lower-level official discretionary decisions; (2) Enforecment involves massive private discretionary decisions; (3) Enforcement involves continuous inputs at key regulatory agencies; and (4) Enforcement is countered by a strong recalcitrant government defendant. The paper concludes by explaining the empirical results in terms of recent behavioral theories of social reform groups. (Author/JM)