  The emergence of dynamical structures in multi-agent systems is analysed.
Three different mechanisms are identified, namely: (1) sensitive-dependence and
convex coupling, (2) sensitive-dependence and extremal dynamics and (3)
interaction through a collectively generated field. The dynamical origin of the
emergent structures is traced back either to a modification, by interaction, of
the Lyapunov spectrum or to multistable dynamics.
