AbstractSynthetic base oil components include mainly polyalphaolefins (PAO), dicarboxylic acid esters and polyol esters. In 1977, the world‐wide share of synthetic oils was about 0.5% of lubricant sales; today this is about 2%, and further annual growth rates of between 10 and 20%—relative to present consumption levels—are expected. The motor vehicle share of the synthetic oil market is about 30%, with the trend rising. In recent years, the literature has contained numerous reports on the general advantages and disadvantages of carboxylic acid esters. This standard knowledge is not repeated here. A few special and relatively new aspects are discussed, based on work carried out at VEBA Öl AG and Chemische Werke H