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The ability of two polymers, Eudragit RL100 and Eudragit RS100, to form a film which would act as a wound dressing yet also release the drug metronidazole into the wound at varying rates has been studied. Films were prepared from the individual polymers, and equal proportions of the two polymers, by dissolution in dichloromethane, addition of the plasticiser dibutyl phthalate and subsequent solvent evaporation. The films were subjected to tensile testing and tear testing. This is important because the films must not be so fragile that they cannot be handled with ease. Water absorption, water vapour absorption and water vapour permeability for each film formulation was determined. The films must be able to absorb moisture yet retain a high humidity at the wound film interface, to be a suitable dressing. The physical structure of the films was examined by scanning electron microscopy. The presence of crystallinity within the polymer structure was investigated by X-ray crystallography. The glass transition temperature of the polymer films was determined by two methods differential scanning calorimetry and dynamic mechanical testing. The dielectric properties of the film samples were also examined. The release of metronidazole from the films into aqueous buffer was monitored. The films manufactured from the polymer Eudragit RL100 have a faster drug release rate than those films manufactured from Eudragit RS100 polymer. The films prepared from an equal proportion of both polymers have a drug release rate between that of the individual polymers. Films produced from the Eudragit RL100 polymer have greater strength than those films produced from the Eudragit RS100 polymer. The strength of the films produced from both polymers lies between that of the individual polymers. The drug appears to act as a plasticiser, and increasing the concentration of the drug increases the mechanical strength, confirmed by the values of the glass transition measurements. Films produced from the Eudragit RL100 are more permeable and capable of absorbing more moisture than films produced from the Eudragit RS100 polymer, whilst films produced from both polymers produce results which lie between those of the individual polymers.