Abstract: Methods of treating, reducing and inhibiting the appearance of ageing in the skin are provided. Also provided are uses and methods of maintaining a youthful appearance, reducing an appearance of ageing, inhibiting an appearance of ageing, reducing a rate of an appearance of ageing, reducing a skin inelasticity, reducing a rate of increasing skin inelasticity, maintaining a skin elasticity, and increasing the density of hair follicles of a skin of a subject comprising applying a granzyme B inhibitor to the skin of the subject. Also provided are methods of identifying a granzyme B inhibitors and agonists.