An improved Kinetic Monte-Carlo (KMC) algorithm for the simulation of atom configuration kinetics in intermetallics is introduced. In KMC a set of jump probabilities is computed from energy barriers. In transition state theory the barrier height is the difference between the initial equilibrium state and a saddle point state. It is on the latter that traditional treatments have made the most far-reaching assumptions, mostly setting it constant. A more detailed treatment of the saddle point state based on ab initio calculations of the actual jump profiles is proposed and demonstrated in Ni 3 Al. It is shown in preliminary KMC simulations that individually computed saddle point energies make a considerable difference in jump statistics and overall kinetics of the long range order parameter.