ABSTRACTMolecular dynamic computer simulations have recently provided some very graphic portrayals of how model lattices can surmount nucleation barriers of various types and accomplish certain kinds of first order displacive transitions. A survey of the different two-and three-dimensional transformations observed to date, along with relevant details about inter-atomic potential, potencies of nucleating defects and preferred transformation paths will be presented. The simulation of other types of first order transformation in solids, such as melting and allotropic transformations will be touched upon. Methods by which a close representation of martensitic transformations in real systems should be obtainable will be discussed.