Atomistic simulation results of the (γU, βZr) solid solution behavior are discussed, including the behavior of the lattice parameter and coefficient of thermal expansion as a function of concentration and temperature. Output from these calculations is used to study the surface structure of U-Zr for different crystallographic orientations, determining the respective concentration profiles, surface energy, and segregation behavior. The segregation of Zr to the surface and overall composition of the near-surface region is studied as a function of concentration and temperature.