The adhesion of electrolessly deposited Ni(P) on alumina ceramic substrates which were coated with thin SiO2, SnO2, TiO2, Al2O3, Y2O3, ZrO2 and (In,Sn)O-x (ITO) films was studied. The adhesion was measured with the aid of the 90 degrees peel test. Strong adhesion of Ni(P) was found for the substrates with ZrO2 and Al2O3 coatings and weak adhesion for the substrates with SiO2, TiO2, SnO2, Y2O3 and ITO coatings. The fracture path and the type of interfacial bonding were analysed using scanning electron microscopy, energy-dispersive analysis of X-rays and X-ray photoelectron spectroscopy. In the case of the strongly adhering samples, fracture took place through the metal layer and along the interface. In the case of the weakly adhering samples only interfacial failure was observed between the Ni(P) layer and the metal oxide coating. Cross-section transmission electron microscopy studies of the interfaces suggested that the differences in peel energy values are caused by differences in micromechanical interlocking at the metal oxide-Ni(P) interface. In addition, a weak boundary layer which was found to be present at the Ni(P)-alumina interface was absent in the case of the strongly adhering samples with the ZrO2 substrate coating.