Black churches represent the fourth largest religious group of congregations in America, behind only Catholic and predominantly white mainline and evangelical Protestant churches. Yet they are often as invisible to the majority of Americans as the disproportionately poor communities many serve in the nation’s cities. Until, perhaps, they are no longer there. Anyone who cares about struggling city neighborhoods needs to pay attention to a major trend unfolding across urban America. Some large black churches are moving out, and many more may follow.