This article estimates the impact of collective-bargaining legislation on disputes during labor negotiations in the U.S. public sector. We use a large national sample of U.S. state and local government contracts to compare the incidence and intensity of disputes by similar workers under different forms of collective-bargaining legislation. The breadth of our data allows us to examine the impact of five different forms of legislation. Our principal finding is that dispute costs are highest in jurisdictions that provide no explicit framework for bargaining or dispute resolution. Strikes are as frequent and as long when they are illegal and employers are not required to bargain with employees as when they are legal but employers are required to bargain. Arbitration is most frequently used when formal institutions for arbitration have been provided.