This chapter focuses on social sets or groups and, in particular, on those constituted by rules of filiation and affiliation. Like other kinds of social group, these may or may not be right- and duty-bearing units, that is jural entities, and if they are jural entities the rights attached to them may be either special or general or both. Social groups and other culturally constituted kinds of entity may be treated jurally as person-like by attributing to them some of the same jural capacities. Perhaps the most person-like kind of jural entity is the kind described in Western legal terminology as corporate. A jural aggregate, like a jural collectivity, is a set of persons each of whom has a similar right, either general or special, but it differs from a jural collectivity in that none of its members may act on behalf of or represent the interests of the others.