The vibrational relaxation of ICN at the surface of chloroform is studied using classical molecular dynamics computer simulations and is compared with the same process in the bulk liquid. Non-equilibrium classical trajectory calculations and equilibrium force correlation functions are used to investigate the factors that control the vibrational energy relaxation rate. We find that the relaxation rate depends on the initial excitation energy and is a factor of three slower at the interface than in the bulk. In addition, the frequency dependent friction at the interface is found to be orientation dependent, reflecting strong inhomogencity. (C) 2002 Elsevier Science B.V. All rights reserved.