In telling the story of why the Jews left and the Catholics stayed, Gerald Gamm places neighborhood institutions - churches, synagogues, community centers, and schools - at its center. He challenges the long-held assumption that bankers and real estate agents were responsible for the rapid Jewish exodus. Rather, according to Gamm, basic institutional rules explain the strength of Catholic attachments to neighborhood and weakness of Jewish attachments.

Because they are rooted, territorially defined, and hierarchical, parishes have frustrated the urban exodus of Catholic families. And because their survival was predicated on their portability and autonomy, Jewish institutions exacerbated the Jewish exodus.