Using the criterion of mutual nomination, 48 children (23% of the sample) who participated in the study had at least one reciprocal best friendship with another participating child; four of these children had two reciprocal best friendships. This rate of reciprocated friendship nominations is similar to that obtained in Hayes, Gershman, and Bolin's (1980) study that established reciprocity of friendship in preschool children through the use of both child and parent interviews and observation of children's play. However, as there were no data available for non-participating children in the current study, the rates of reciprocated best friendship should be treated with caution, i.e., a participating child may indeed have had a mutually recognized best friendship, but with a child who did not participate and hence for whom nomination data were not available. In such cases, friendship reciprocity could not be established based on the available best friendship nominations and so could not be included in the count of reciprocated best friendships.