The present invention relates to the use of a water soluble lactone-derivative as a solvent in agrochemical formulations, as well as to such formulations per se in both concentrated and dilute form, and methods of making such formulations. In particular the invention relates to such formulations (and more specifically still, emulsifiable concentrates and/or emulsions or microemulsions) comprising a lactone derivative having six-carbon atoms and at least one pesticidally active agrochemical ingredient selected from the group consisting of a herbicide, safener, insecticide, fungicide, nematicide, molluscicide, and a plant growth regulator.
