Coupled advances in empirical force ®elds and classical molecular dynamics simulation methodologies, combined with the availability of faster computers, has lead to signi®cant progress towards accurately representing the structure and dynamics of biomolecular systems, such as proteins, nucleic acids, and lipids in their native environments. Thanks to these advances, simulation results are moving beyond merely evaluating force ®elds, displaying expected structural¯uctuations, or demonstrating low root-mean-squared deviations from experimental structures and now provide believable structural insight into a variety of processes such as the stabilization of A-DNA in mixed water and ethanol solution or reversible b-peptide folding in methanol. The purpose of this overview is to take stock of these recent advances in biomolecular simulation and point out some common de®ciencies exposed in longer simulations. The most signi®cant methodological advances relate to the development of fast methods to properly treat longrange electrostatic interactions, and in this regard the fast Ewald methods are becoming the de facto standard.