Selective functionalization of naturally occurring monoterpenes can provide oxygenated derivatives, which are commercially important materials for perfumery, flavor, and pharmaceutical industries. We have, in recent years, been exploring the application of metal complex catalytic systems for the selective oxidation and carbonylation of various monoterpenes, such as limonene, α-pinene, β-pinene and camphene. We have also studied the heteropoly acid catalyzed hydration/acetoxylation of some monoterpenes. In the present paper, recently published results on the following transformations of monoterpenes are reviewed: palladium/tin catalyzed alkoxycarbonylation, platinum/tin catalyzed hydroformylation, palladium catalyzed oxidation by dioxygen and by hydrogen peroxide and heteropoly acid catalyzed hydration/acetoxylation.