Many technologies rely on heterostructures made of materials with very different chemistries. Heterostructures are often out of equilibrium due to the close proximity of very different chemistries. This results in the evolution of the heterostructure with a concomitant degradation of its functional capabilities over time. Predicting the evolution of heterostructures consisting of widely differing chemistries remains one of the biggest challenges in materials science and requires a description of processes that span widely varying length and time scales. The processes that dominate heterostructure evolution are common to most other non-equilibrium processes in the solid state. This project will lead to the development of an openly distributable framework that rigorously integrates theory, experiment and computation to predict and elucidate the evolution of complex materials heterostructures. It will address an important challenge within the Materials Genome Initiative of linking the electronic structure of the constituent chemistries of a complex materials system to its behavior at technologically relevant length and time scales.