Abstract: The present invention provides an improved antimicrobial composition which includes at least one quaternary ammonium compound and nerolidol. The nerolidol component of the composition provides enhanced antimicrobial efficacy, even when used in small amounts. Further, the nerolidol component provides such enhanced antimicrobial efficacy that the quaternary ammonium compound may be used in reduced amounts as compared to the amounts used for antimicrobial effect in prior formulations. The enhanced antimicrobial composition of the present invention is especially useful in cleaning or disinfecting applications, such as the cleaning of hard surfaces.