Abstract The method of Dykstra-Parsons, originally developed to model water flood performance, has been adapted to screen reservoirs for their Chemical / Polymer Flood suitability. Firstly, this paper summarises Dykstra-Parsons’ Theory alongside an automated method of tuning reservoir layer properties to [pre-chemical] water flood performance. (Methods of determining both layer permeability and oil-phase relative permeability end-points, from water-cut development, are presented.) Secondly, this paper describes the adaptation of Dykstra-Parsons’ Water Flood theory to model both chemical flood and post-chemical flood production performance. Permeability adjustment, mobility control, and alkaline-surfactant flood models are discussed.