Developing and applying production chemicals in subsea oilfields located in environmentally sensitive areas has a number of challenges. First production chemicals used in these oilfields are required to have a good ecotoxicological profile. Ideally they must be biodegradable and either have reduced toxicity or be non-bioaccumulative. Furthermore in certain instances production chemicals that are applied in subsea systems are required to conform to stringent standards to prevent blockages of chemical injection systems and umbilicals.For an oilfield located in the Norwegian sector of the North Sea there was a potential of BaSO4 scale formation to occur shortly after the onset of seawater break through. Scale prediction studies indicated that if not treated effectively scale would deposit in the subsea safety valves production chokes and subsea booster pumps. Therefore an effective environmentally acceptable scale inhibitor was required to mitigate scale subsea. In addition the scale inhibitor was required to conform to standards normally associated with products used in deepwater fields. These standards specify that a subsea product should possess key physical properties that include having a low viscosity at typical sea bed temperatures and injection pressures compatible with produced water not contain micro solids or particulates be stable for pro-longed periods at sea bed and injection temperatures and be resistant to hydrate formation.This paper describes the work carried out to develop an effective scale inhibitor that is environmentally acceptable and is also suitable for subsea deployment. The paper also details the challenges encountered when developing a product for such an application.