There is provided an anti-fouling composition comprising (i) a surface coating material； (ii) an enzyme obtained or obtainable from a marine organism； and (iii)(a) a substrate for the enzyme； and/or (b) a precursor enzyme and a precursor substrate, wherein the precursor enzyme and the precursor substrate are selected such that a substrate for the enzyme is generatable by action of the precursor enzyme on the precursor substrate； wherein the enzyme and the substrate are selected such that an anti-foulant compound is generatable by action of the enzyme on the substrate.
