The concept of team formation, or joint action, is central to a wide variety of disciplines including organizational design, computational organization theory, planning and learning in multi-agent systems, and distributed artificial intelligence. One key feature of team formation is the underlying social network topology which determines the direct interactions among the individuals of the organization. Traditional models of social phenomena have been restricted to regular lattice, or fully-connected, network topologies, but recent results have shown that real-world networks have much different and much richer structure.