This chapter is concerned with natural wines made from Vitis vinifera and Vitis labrusca grapes. Fruit wines, fortified wines, whether flavored or not with aromatic herbs, and wines made from cereals are therefore not includes. From the large body of literature on wine volatiles, all the information concerning compounds contributing to the characteristic flavor of wines has been gathered. This information has been classified according to the chemical classes of compounds found in wine, which will be treated successively: esters, alcohols, acids, lactones, carbonyl compounds, acetals, phenols, sulfurcontaining volatiles, nitrogen-containing volatiles, and miscellaneous substances. The Esters are qualitatively the major constituents of wines and are also, in addition to water, ethanol and fusel alcohols, major quantitative constituents. Various nitrogen molecules have been reported in the volatile composition of wines. Polysulfides such as dimethyl disulfide do not appear to contribute to the aroma of wines.