This paper reports on a pilot study designed to investigate how regulating group size or social density, in the form of peer-dyad intervention, may contribute to peer interaction in children who have severe language disorders. Subjects were five males and one female ranging in age from 42-48 months all of whom had a severe developmental delay in all areas of language acquisition as well as a lack of social-pragmatic behaviors. Subjects were paired in three dyads and observed over a 6-month period in both their dyads and whole group for the frequency of several categories of nonverbal interactional behavior including initiating, imitative, and reciprocal behaviors. Of the 480 minutes of observation data, subjects engaged in non-interactional behavior for a total of 307 minutes. A total of 1,160 events of interactional behavior were observed. Of that, 322 events occurred in the whole group context and 838 in the peer-dyad context. The frequency of interactional behavior over the eight observation periods followed a complementary pattern, increasing and decreasing in frequency in a reciprocal fashion. Results support the value of the peer-dyad for the development of interactional behavior for the language impaired child. Contains 23 references. (DB)