This invention relates to ultrasound delivery apparatus comprising flexible arrays of transducers and to methods and topical compositions for the treatment of skin, in particular for the treatment of cosmetic skin conditions and to improve the appearance of sun damaged and/or aged skin; the invention further relates to the use of such apparatus and compositions in methods of treating skin, which methods may incorporate the application of ultrasound. The composition may comprise one or more anti-gfycation agent, one or more anti-oxidant, a dermatologically acceptable excipient and optionally one or more substance capable of inducing expression of a molecular chaperone.