The state of the art in research on chirality and odor is presented, with special emphasis on synthetic and analytical methods. The syntheses of l-octen-3-ol enantiomers, of chiral alkan-2-yl esters, of "whisky lactone," and of chiral sulfur compounds, known as characteristic components of the yellow passion fruit, are reviewed. It is demonstrated that optically pure stereoisomers exhibit their own, specific sensory characteristics. Therefore, stereoisomers of very high enantiomeric excess (ee) must be achieved for valid evaluations of their structure-function relationships. Analytical methods for stereodifferentiation of chiral flavor compounds and recent developments in biotechnology are discussed.