The effects brought about by introducing both a stabiliser cation and a potentially promoting oxide phase, namely lanthanum and tin oxide, respectively, on a conventional support for Pd-based catalysts for methane combustion were evaluated. The characteristics of both supports and catalysts were analysed by XRD, LRS, XPS and PdO decomposition; their catalytic activity was evaluated in the combustion of methane under lean conditions (O-2/CH4 = 4). The behaviour of these systems were also evaluated after high temperature treatment, carried out under conditions similar to those created during the combustion of methane. The results shown that the addition of tin and La on PdO/Al2O3 improves the thermal stability of Al2O3 and PdO but did not bring any benefit to activity in methane combustion. (C) 2003 Elsevier B.V. All rights reserved.