A process for making microcapsules of an oil which are in dispersion in water comprises the steps of; (i) forming an initial dispersion of the oil in water in the presence of a surfactant, (ii) heating the initial dispersion above its phase inversion temperature, to form a bicontinuous phase composition, (iii) allowing or causing the composition to cool to below the phase inversion temperature so as to form an emulsion of oil droplets in the water, and (iv) encapsulating the oil droplets. The oil preferably has dissolved in it an oil-soluble or oil-dispersible active ingredient selected from agrochemicals, cosmetics, fragrances, sun-screens, ink-jet dyes, pigments, toners, biocides and pharmaceutical and veterinary products including drug delivery systems.