Charged polymers and, in particular, polyelectrolytes are of great interest, but our understanding has been much poorer in comparison with neutral polymers. The interest in polyelectrolytes is strong, because many biopolymers such as DNA are polyelectrolytes, and also synthetic polyelectrolytes have important commercial uses. Part of the difficulty in treating polylectrolytes resides in the Coulomb interactions. Recently, molecular dynamics simulations have proven to be a valuable tool in over-coming some of these challenges and have fundamentally enhanced our understanding of polyelectrolytes. These simulations are based on the bead-spring model that has been successively applied to neutral polymers. To model polyelectrolytes, monomers may now be charged, and solvent ions are introduced and treated explicitly. The long ranged Coulomb interaction is treated by a particle-mesh Ewald method. Results of these simulations will be discussed. The structure of a polyelectrolyte chain as a function of concentration, added salt and charge distribution has been calculated. A variety of phenomena have been encountered in these simulations and will be discussed. These include counterion condensation, ion capture and bundle binding. No aggregation occurs for monovalent counterions. ©2000 American Institute of Physics.