A metaphor of classical social theory concerning the “intersection” of persons within groups and of groups within the individual is translated into a set of techniques to aid in empirical analysis of the interpenetration of networks of interpersonal ties and networks of intergroup ties. These techniques are useful in the study of director interlocks, clique structures, organizations within community and national power structures, and other collectivities which share members. The “membership network analysis” suggested in this paper is compared to and contrasted with sociometric approaches and is applied to the study by Davis et al. (1941) of the social participation of eighteen women.