This paper reported a pilot study on issues relevant to the social development of the 2-year-old child and discussed the results within the framework of the evolutionary-control-systems theory proposed by Bowlby (1958, 1969) and Ainsworth (1967, 1969). The issues examined were (1) attachment and (2) reciprocity, or the ability of the child-mother unit to work together under a single goal-hierarchy. Hypotheses were proposed that dealt with (a) the stability of attachment, (b) maternal variables which would serve as the optimal setting for the further expression of attachment behaviors, (c) the nature of the child's ability to carry on transactions with his mother which could be labelled reciprocal, (d) maternal variables which would serve as the optimal setting for this development, and (e) the relative nature of attachment and reciprocity. Subjects were three boys and three girls from white, middle class homes. Data were collected by means of naturalistic observations in the home, supplemented by two standardized situations. Infant and maternal rating scales were used for analysis. Study findings were discussed in terms of Bowlby's theories and suggest that parents should provide the child with stable and workable behavior models on his level of ability. (NH)