This edition has been comprehensively updated to reflect current research results on the chemistry, physics and cosmetic behaviour of hair. The book provides a detailed scientific presentation of the mechanisms of action of hair care products. It includes background information on hair morphology, the biochemistry of keratin proteins, and the interaction of numerous chemical products with hair, including detergents, bleaches, waves, dyes and conditioners. New polymers used in hair care are discussed. Numerous electron micrographs are provided of hair fine structure, as well as micrographs of structural anomalies.