Summary. The growth of Staphylococcus aureus 111 was inhibited by aliphatic alcohols. The extent of inhibition by primary n-alcohols increased with the elongation of the chain. Secondary alcohols were less inhibitory than the corresponding primary alcohols. The inhibitory effect was influenced by the distance of the hydroxyl group from the end of the carbon chain. When the alcohols were added to the medium in sub-inhibitory amount, enzyme synthesis by the bacteria was decreased, but there was no demonstrable inhibition of enzyme already formed.