This study details three methods developed during the course of an investigation for describing adult-child interaction: (1) the "VINEX" category system for coding the actual language of the adult and the child; (2) a coding system for describing nonverbal behavior; and, (3) "Interaction Language," for the use of an observer in narrating the adult-child interaction. The test materials were small samples of mother-child pairs from New York City--one from West Harlem (with a middle and lower class subsample), and the other from Washington Square (white upper middle class). The empirical findings of the study were as follows: (1) the general pattern of mother-child interaction was a responsive one--a give and take interaction which was not balanced, but at the same time not markedly one-sided; (2) changes in interaction with age appeared to be partly due to the child's cognitive development, increase of explanations, and increased grammatical complexity for example; (3) the differences between the West Harlem and the Washington Square samples, as well as the difference between the lower and middle class West Harlem sample appeared to be small; and, (4) commonly held stereotypes of the family interaction of Harlem children were not supported by any of the data of the study. Appended are manuals on the methodology developed, extensive tabulations of test results, and interview formats used. (RJ)