Multiscale Designer is an accurate and efficient tool for development of multiscale material models and simulation of parts manufactured from any heterogeneous material; including, but not limited to, continuous and chopped fiber composites, honeycomb cores, lattice structures, reinforced concrete, soil, bones, etc... Applications include multiscale material modeling for design, ultimate failure assessment, statistical-based material allowables, creep, fatigue, fracture, and impact simulations; and provides user material plugins to commercial FEA solvers, Optistruct, RADIOSS, LS-DYNA, and Abaqus, for the simulation of any part using multiscale material models.