Atomistic, coarse-grain, and mesoscopic computer simulation methods applied recently to the study of block copolymer assemblies in solution are reviewed. At the atomic level, particle-based simulations have provided insight into specific interactions such as hydrogen bonding between polymer and water. Coarse-grain models have given a generalized view of the conformations of polymer chains in solvents of different qualities by grouping clusters of atoms into effective interaction sites. Mesoscopic self-consistent field theory allows for the study of the phase diagram of block copolymers in water using a mean-field continuum description. Advances in and results with these methodologies are presented along with present challenges. (c) 2006 Wiley Periodicals, Inc.