Main goal of this study is to achieve superb catalytic performance by using atomically monodisperse clusters dispersed on technologically relevant oxide supports - prerequisites to produce highly uniform active sites. I. ODHP. Pt8-10 clusters supported on alumina coated mesoporous anodized aluminum-oxide membranes with and without SnO promoter were studied. Only CO2 or CO2 +CO byproduct(s) were detected. Per Pt-atom activities 103-104 times higher than per V-atom activities of reference VOx catalysts were observed. Up to 95% propane conversion and maximum 85% selectivity towards propene at 400-550°C demonstrate the advantage of spatially localized metal loading. II. Oxidation of Alkenes. Oxidation of ethylene and propylene on Au7-10 and Ag15-19 clusters and ∼1nm size nanoparticles on alumina films were studied by unique combination of simultaneous mass spectrometry and grazing incidence small-angle X-ray scattering. Evolution of products and nanocatalysts' size&shape as a function of temperature & time during the catalytic reaction will be discussed.