We compare the efficiency of three stochastic optimization methods, simulated annealing, parallel tempering and stochastic tunneling to locate the global minima of complex and rugged potential energy surfaces arising from atomistic models for receptor-ligand docking. The stochastic tunneling method proves to be the most efficient generic approach for atomistic receptor-ligand docking in the rigid ligand -rigid receptor approximation. (C) 2002 Elsevier Science B.V. All rights reserved.