Hardness response of electroplated nickel coatings on copper substrates was studied over a range of applied loads and two decades of indentation depths. The hardness values were determined experimentally using a combination of conventional Vickers testing and microhardness measurements. The results were analysed using the work-of-indentation model for the hardness of coated systems, which was originally proposed and applied by the authors to the study of hard ceramic layers on steel substrates. The analysis shows the generality and flexibility of the model, which allows both brittle and ductile modes of response to be described with equal success. (C) 2000 Elsevier Science S.A. All rights reserved.