Belonging and the sense of belonging are vital factors of human identity, loyalty, and roles, the expectations we have of ourselves and of one another. The boundaries, social and sexual, that all human societies deploy to protect personal privacy and personal and group dignity are modulated by our sense of belonging and often by a complementary sense of difference. The bonds of affinity and the corresponding sense of belonging that modulate our norms and roles are perhaps most visible in the striking colorations they assume in the eyes of outsiders viewing the mores of traditional societies. But the vital necessity of a sense of shared identity is all the more critical when social identities are fragmented by faction, tribalism, or racism, or when anomie and alienation have sapped the sense of commitment that energizes collaborative efforts in any human group. Few dimensions of personal outlook and awareness are more powerful in communal, legal, or political settings than the sense of belonging, that curiously shared identity by which we bind ourselves and one another to shared goals and values in some version of the sense that we are one.