Abstract: A composition and method for modifying filamentous keratins. Filamentous keratins are contacted with an effective amount of a modifying composition consisting essentially of:from about 58 to 60 weight percent water;18 to 20 weight percent milk protein product;6 to 6.25 weight percent polysaccharide;5 to 6.5 weight percent sodium hydroxide;4.75 to 5.25 weight percent polyglycerol;4.75 to 5.25 weight percent aqueous collagen polypeptide/amino acid solution; and0.075 to 0.095 weight percent polysorbate-80.The composition is allowed to remain in contact with the filamentous keratins for a period of time sufficient to effect modification thereof. The composition is then removed from the filamentous keratins, and the keratins are cleansed by contact with water-soluble cleansing composition, which cleansing composition is removed after cleansing is effected. The composition and method and particularly efficacious in the straightening of filamentous human keratins.