This invention relates to compositions suited to use as hair shampoos, and particularly those developed with a view to the treatment of a hair borne infestation, or of a skin disease of the scalp in addition to the primary purpose of hair cleaning and conditioning. In a first aspect of the invention there is provided a substantially non-aqueous liquid shampoo composition comprising at least one detergent, at least one active agent incompatible with water, an organic bulking agent and shampoo excipients, said organic bulking agent being miscible with water and miscible with said at least one detergent and shampoo excipients. It has been surprisingly found that replacing an aqueous bulking agent such as water with an organic compound which is compatible with active agents insoluble in water but which itself is miscible with water and miscible with detergents can produce a cosmetically and aesthetically acceptable non-aqueous liquid shampoo, particularly one having acceptable foaming characteristics.