The present invention relates to a composition for treating wood comprising a wood preserving compound and a carrier, wherein the carrier is an emulsion comprising a hydrophobic phase, a hydrophilic phase and a surfactant system. In particular, the surfactant system comprises a non-ionic polyethoxylated alkyl amine and an anionic C10-C16 alkylbenzene sulfonate. Methods of using the composition to treat wood, especially timber, are also described.
