This study determined the sociometric status of "referred" children (with emotional and/or learning problems) and "stable" children enrolled in a mainstreamed preschool program in an effort to determine whether mainstreaming affects the social interaction among preschoolers functioning at different developmental levels. Two separate experiments were conducted. In the first, 16 preschoolers (7 referred and 9 stable) were interviewed individually on two consecutive school days. Individual pictures of each child arranged randomly on a bulletin board were used in conjunction with a questionnaire to determine the sociometric status of each child (the child pointed to individual pictures of one or more children in response to the interviewers questions). In the second experiment, the subjects were the same preschoolers plus two new children (8 referred and 10 stable). The choice of classmate of each child was recorded turn chose a classmate to line up with for outdoor play). The degree of cross-group interaction and acceptance/rejection level was determined by an analysis of the choices of the first five children of each day. The results of both experiments supported the hypothesis that cross-group social interaction does exist among mainstreamed preschoolers functioning at different levels. Social acceptance or rejection of the child apparently was not due to his/her developmental level, but to the interaction of other variables. (CM)