The new revolution in nanoscience, engineering, and technology is being driven by our ability to manipulate matter at the molecular and supramolecular level to create “designer” structures. The parameter space for engineering new materials is indeed vast—structures vary drastically with small changes in interparticle interactions or with small changes to the conditions under which the material is synthesized. Computational simulation offers a means to discover the fundamental principles of how nanoscale systems of molecular building blocks self-assemble, and how we might control the assembly process to engineer new materials.