From the early 1800s through the middle of the twentieth century, U.S. democracy was energized by the remarkable propensity of Americans to organize and join voluntary associations. Observers of many persuasions agree on this point – and also concur that the final decades of the twentieth century brought fundamental shifts in civic organization and citizen involvements with voluntary groups in the United States. The nature, tempo, and causes of these changes remain a topic for scholarly discussion, however. Investigators highlight different aspects of recent civic transformations and explore these changes using contrasting theoretical perspectives and types of empirical data.