The effects of different levels of cooperation on cross-handicap interaction were Compared in two studies. In the first study 72 sixth-grade students were randomly assigned to three conditions (cooperative controversy, cooperative debate, and individualistic) stratifying for sex, ability level, and handicap. They participated in the study for 55 minutes a day for 11 instructional days. In the second study, 51 fourth-grade students were randomly assigned to two conditions (intergroup cooperation and intergroup competition) stratifying for sex, ability, and handicap. They participated in the study for 55 minutes a day for 10 instructional days. An Activity Report Scale was given to students to determine who they interacted with in structured class activities, unstructured class activities, school activities outside of class, and activities in the home. The results indicated that pure cooperation promoted more frequent cross-handicap interaction than did a mixture of cooperation and competition. The interaction patterns formed within cooperative learning situations generalized into unstructured class and school activities.