FRIENDSHIPS and romantic relationships are especially impor-tant during adolescence for managing self-identity, intimacy, andother developmental issues (Bell, 1981; Douvan & Adelson, 1966; Erikson, 1968; Thornburg, 1975). But, it is not enough to explain friendships and romances solely as functions of identity management; nor is it sufficient to use a two-person model, for these intimate relationships do not develop in a vacuum (Parks, Stan, & Eggert, 1983). They are "set in a nexus of other relationships, and may be influenced by the relationships that each participant has with other individuals" (Hinde, 1981, p. 15). Accordingly, this study considers the role of one social structural phenomenon, communication networks, in the development of adolescents' personal relationships. Particularly, it compares the associations between communication network involvement and the dynamics of two types of personal relationships: adolescents' close same-sex friendships vis-a.-vis their cross-sex romantic relationships. Its central hypothesis is that the

dynamics of adolescents' existing friendship and romantic relationships are positively and reciprocally associated with communication network involvement (Duck & Gilmour, 1981b; Parks, Stan, & Eggert, 1983; Ridley & Avery, 1979).