This research was supported by the Center for Coordination Science at the Massachusetts Institute of Technology and by a fellowship from the Ameritech Foundation through the Information and Organizations Program of the University of Michigan Institute for Public Policy Studies. The author thanks Brian Pentland, Michael Prietula, and Thomas W. Malone for their comments on earlier drafts of this chapter. This work has also benefited from discussions and suggestions from members of the Process Handbook Project, in particular, George Wyner, Gilad Zlotkin, George Herman, and Martha Broad.