In this book, scholars and church and synagogue leaders examine religious affiliation in contemporary America. Their essays explore the dynamics of congregational affiliation: the motivations which impel people to join a congregation, drop out or remain unaffiliated; the practices within churches and synagogues which attract or repel membership; and the ways in which contextual religious, social, and cultural factors influence patterns of congregational affiliation. The book is principally concerned with churches and synagogues in the more liberal denominations of Christianity and Judaism, those where the greatest membership losses are occurring. Over the past few decades membership in mainline churches in the United States has declined, with some groups losing more than 20 percent of their membership. Similarly, four decades ago, 60 percent of all American Jews were religiously affiliated; today that number is below 40 percent. This book seeks not only to explain the reasons for declines in affiliation, but also to propose approaches that may combat the decline and showcase studies of congregations that have succeeded in holding their memberships. This work will be of great interest to scholars of religion in America as well as clerics, rabbis, and others actively involved in congregational life.