The basic methods used in the computer simulation of the atomic structure and structural changes of defects in metals--molecular dynamics, variational procedures, and the lattice statics method--are briefly reviewed. There is a discussion of some new interatomic potentials, in particular, potentials which incorporate the partially filled d shells of transition metals. Some typical results of the calculations of the atomic structure of defects and their formation and migration energies are reported. These results refer to mixed dumbbells, complexes consisting of a vacancy and an impurity atom, clusters of vacancies and interstitial atoms, and dislocation cores in bcc and hcp metals, including transition metals, and in alloys with a long-range order; special grain boundaries; defects in void superlattices in irradiated metals; and point defects in amorphous metals. The future outlook for simulation is discussed.