Abstract: Aqueous pesticidal suspensions comprise: (a) 5 to 40% w/v of (i) a pesticide having a melting point in the range of from 50 to 120° C. and a solubility in water of not more than 0.2% w/v or (ii) a mixture of the pesticide (i) and one or more other pesticides having a melting point of at least 50° C. and a solubility in water of not more than 0.2% w/v in the ratio of at least 1 part by weight of the pesticide (i) to 10 parts by weight of the other pesticide or pesticides, (b) 2.5 to 20% w/v of a non-ionic alkoxylate surfactant, (c) 0.5 to 5% w/v of a naphtalene sulphonate-formaldehyde condensate, (d) 0.1 to 5% w/v of a non-ionic polymethyl methacrylate-polyethylene oxide graft copolymer, (e) 0 to 25% w/v of other additives, and (f) water in sufficient amount to bring the total composition to 100% w/v. Pesticidal suspensions formulated in this way show less variation in viscosity than hitherto.