The authors surveyed public libraries to learn about the opportunities for play they offered and children's freedom to engage in such play without adult supervision. The authors conclude that, in recent years, public libraries in the United States have increasingly created spaces and programs enabling free play for children and teens. These include "maker spaces" (for constructive play), playrooms with toys and games for young children, and rooms where teens can socialize and play games. The authors describe the survey results and three especially successful library play programs in detail. These results, they conclude, illustrate how librarians have welcomed children and enabled free play in the library through policies of nonintervention and by emphasizing nonintervention by care givers who might otherwise intervene in such play.