The performance of Pt-gamma-Al2O3 and CuZSM5 de-NOx catalysts was evaluated at the exhaust of a lean-burn gasoline engine. It is shown that durability for zeolite catalysts and N2O formation for Pt catalysts are the main limitations which have to be still overcome to successfully apply the lean de-NOx technology. (C) 2000 Elsevier Science B.V. All rights reserved.