If strong social identities, which create clear boundaries between in-groups and out-groups, are more effective in retaining and recruiting members and increasing the salience of in-group identities, why, and under what circumstances, do groups persist in formulating weak, and ambiguous group identities and group boundaries? What is to be gained by boundary resistance? Drawing on ethnographic fieldwork at a liberal congregation, I demonstrate that "weak" boundaries, rather than representing merely the absence of strong boundaries, represent an achieved identity, requiring effort and intention on the part of both parishioners and church leaders to sustain. If we are to analyze group means for boundary maintenance, I argue that we must also analyze group processes and motivations for boundary disruption and decay.