The review gives an analysis of the present position of catalyst research aimed at solving ecological problems (ecological catalysis) in the cleaning of motor vehicle gas emissions. The analysis is based on data from the scientific and technical literature of the last five years. Information is given on existing and planned standards for the regulation of emissions in the most developed countries of the world. Attention is concentrated chiefly on the removal of exhaust gases CO, NOx and H2S in the presence of hydrocarbons. In accordance with modern trends, processes of NOx removal are examined in most detail, including data from studying the mechanism and kinetics of catalytic breakdown, and also the selective catalytic reduction of NO by ammonia. Chemical schemes of the mechanism of corresponding processes in the presence of metal oxide and Cu-substituted zeolite catalysts are discussed. These are interpreted on the basis of data obtained by IR spectroscopy of surface intermediates.