Evans's work has changed the way people think about the statistical mechanics of non-equilibrium systems. He proposed, developed, or verified nearly all of the modern molecular dynamics computer simulation algorithms. He produced the first tractable version of thermostatted nonlinear response theory. He tested this theory and its application to the derived properties of nonequilibrium steady states. Many believe that his Transient Time Correlation Functions provide the key to present day theory and simulation of nonequilibrium systems far from equilibrium. He has resolved a number of long standing paradoxes including Gibbs' problem concerning the conservation of entropy and the van Kampen objection to linear response theory.