Polycarbcxylic acids having three or more carboxyl groups per molecule were used as coreactant curing catalysts with a series of N-methylol crosslinking agents. Strongly acidic, water-soluble acids were found to be effective catalysts for the curing reactions, while less soluble or weaker acids were poor catalysts, as were partially neutralized polycarhoxylic acids. The X-methylol crosslinking agents which responded most favorably to catalysis by the carboxylic acids were those which formed ethers that were most stable to acid-catalyzed hydrolysis. The N-methylol crosslinking reagents which formed ethers less stable to acidic hydrolysis gave poor wrinkle recovery angles when applied to cotton fabrics with carboxylic acid catalysts.