Molecular dynamics simulations of particle impacts on carbon-based materials are described, A number of different semi-empirical, many-body potentials are used and modified to suit the particular problem involved. The simulations include the surface damage, sputtering, and ion reflection from graphite surfaces. The displacement energy thresholds and interstitial formation in graphite is also described. Simulations involving radiation damage in polymers and C-60 film growth on Si surfaces are also considered.