Eugenol and related volatile phenylpropenes, such as isoeugenol and methylchavicol, are important components of many economically important spices. They are also valued for their biological properties. For example, sweet basil, which produces high levels of these compounds in its glandular trichomes, has been used for centuries as a food preservation agent. These compounds are widely distributed in the plant kingdom, and are produced by plants as defense against animals and microorganisms and as floral attractants of pollinators. The final step in the biosynthesis of eugenol and chavicol, catalyzed by an enzyme known as eugenol synthase (EGS), was recently reported by our group. It was found that EGS requires acetate esters of coniferyl and p-coumaryl alcohols, respectively, to form eugenol and chavicol. We have identified in the basil glandular trichomes, an enzyme, coniferyl alcohol acetyl transferase (CAAT), that is able to form these acetate esters. The cDNA for this enzyme was identified from a sweet basil glandular trichome EST database, based on sequence identity to other acyltransferases. Biochemical characterization of recombinant CAAT revealed that the enzyme is optimally active at a biological pH, and shows maximum substrate preference for p-coumaryl alcohol, followed by caffeyl and coniferyl alcohols. Biochemical assays performed with protein extracted from leaf tissue of several basil lines showed analogous CAAT activity. Kinetic data for the enzyme, as well as developmental gene expression and enzyme activity patterns will also be discussed.