Conservation of water resources and the minimization of discharges are paramount in today's industries. The reuse of process water effluents plays an important role in conserving water. This paper investigates the recycle of effluent process water from a metal finishing operation using reverse osmosis to provide make-up water for reuse. A case history demonstrates how membrane separation is used to produce water suitable for use and to minimize or eliminate aqueous discharges. This paper also examines the use of pretreatment chemicals to minimize membrane fouling.