During student riots at Stanford University in the spring of 1970, 164 students (of whom 95 were control subjects with no contact) and 37 local policemen were brought together to facilitate nonviolent interactions and promote understanding between students and police. Three forms of contact were utilized: students riding in police squad cars, police having dinner and “rap sessions” with students, and encounter groups. Self-report questionnaires assessed the attitudes of members of each group toward the other both before and after contact. Significant attitudinal depolarization toward the other group occurred as a result of the three types of contact. These findings are discussed in terms of the reduction of autistic hostility between groups as well as an increase in self-disclosure. Methodological problems inherent in such social action projects are considered and suggestions made for future projects of this kind.