An enzymaticapproach to the synthesis of all the possible stereoisomers of (E) and (Z), cis and trans-γ-irones in enantiomericallypure form from commercial Irone Alpha® is described. A very efficient resolution of racemic trans-γ-irone, affording both the enantiomers in high ee and chemical purity, is also presented. Olfactory evaluation of (+)- and (−)-3b and full configuration assignment of the