We characterize the agreements that the players of a noncooperative game may reach when they
can communicate prior to play, but they cannot reach binding agreements:
A *coalition-proof equilibrium* is a correlated strategy from which no coalition has an
improving and self-enforcing deviation. We show that any correlated strategy whose support is
contained in the set of actions that survive the iterated elimination of strictly dominated
strategies and weakly Pareto dominates every other correlated strategy whose support is
contained in that set, is a coalition-proof equilibrium. Consequently, the unique equilibrium
of a dominance solvable game is coalition-proof.