Stress in crystalline TiN/amorphous B–C–N multilayered thin films has been determined by the substrate curvature technique. It is established that the total stress is dependent on the number of deposited bilayers and on the bilayer repeat length. The linear relationship between the stress and the inverse of the bilayer repeat length allows calculation of the value of the interface stress. It is found to be compressive with a value between 1.79 and2.46 J/m2,depending on the calculation method. An apparent dependence between the interface stress and the total thickness of the multilayer film is observed. It is interpreted as an additional relaxation due to an increase of the roughness of the interfaces when the number of deposited bilayers is increased. ©1997 American Institute of Physics.