Observers evaluated five odors and their 26 mixtures (two, three, four, and five components) by magnitude estimation. Estimates revealed that in mixtures there is moderate suppression of perceived intensity; a vector model proposed by Berglund (Annals of the New York Academy of Sciences, 1974, 237, 35-51) provides a good prediction of the intensity of binary mixtures, but overpredicts the intensity of three, four, and five component mixtures. Hedonic tones of mixtures were difficult to predict from hedonic tones of components. Qualities of mixtures were difficult to predict from quality of components. Intermediacy, of quality and hedonic values, was often observed.