Abstract: Styrene or styrene substituted in the aromatic nucleus or on the vinyl group with a methyl group or styrene having the vinyl group substituted by hydroxymethyl is reacted with less than 2 moles of formic acid and less than 2 moles of hydrogen peroxide per mole of styrene or substituted styrene to hydroxylate the double bond. The formic acid is employed at a concentration between 20 and 100 weight percent and the hydrogen peroxide is employed at a concentration of less than 50 weight %. The concentration of the hydrogen peroxide in the aqueous phase of the reaction mixture is held below 15 weight percent during the entire reaction.The corresponding diols or triols are formed directly from the olefins employed within reasonable reaction times in high yields.