Research suggests that cooperative interactions are associated with enhanced cognitive and affective outcomes. This paper describes eight principles that can be used to promote such interactions among students working in online environments. The principles derive from a well-established approach to education, known variously as cooperative learning and collaborative learning. Each principle is explained as to what it means, why it is important and how it can be deployed. The eight principles are heterogeneous grouping, teaching collaborative skills, group autonomy, maximum peer interactions, equal opportunity to participate, individual accountability, positive interdependence and cooperation as a value.