The strategic principles that enable simple, open-structure solid catalysts to be systematically designed so as to oxidize selectively a wide range of organic compounds in air or oxygen under mild conditions, and often without use of solvent are outlined. Illustrated examples of specific reactions, that utilize single-site catalysts that permit these conversions, include: preferential conversion of cyclohexane to adipic acid, toluene to either benzaldehyde or benzoic acid, linear alkanes to terminally oxyfunctionalized products, alkenes to epoxides, ketones to lactones, methanol to formaldehyde and ammonia to hydroxylamine, the last reaction under in situ conditions. Single-site catalysts open up methods for the future avoidance of ecologically harmful procedures, which are still publicized in modem textbooks, that use aggressive stoichiometric oxidants such as CrO3/H2SO4, pyridinium chlorochromate, SeO2, KMnO4 and KHSO5. (C) 2006 Elsevier B.V. All rights reserved.