In this paper we describe a co-located interface on a tabletop device to support social competence training for children with Autism Spectrum Disorder. The interface has been developed on the multi-user DiamondTouch tabletop device as a 3-user application for two children and a facilitator (therapist or teacher). It takes advantage of the DiamondTouch table’s unique ability to recognize multiple touches by different users in order to constrain interactions in a variety of ways. This paper focus on the support provided by the system to enhance a facilitator’s management of interaction flow to increase its effectiveness during social competence training. We discuss the observations collected during a small field study where two therapists used the system for short sessions with 4 pairs of children. Although limited by the number of participants to date, the interactions that emerged during this study provide important insight regarding ways in which collaborative games can be used to teach social competence skills. Thus the children benefit from the motivational and engagement value of the games while the facilitator gains access to new tools to intrinsically support and shape the session.