ABSTRACT Asphaltene deposition has a significant detrimental effect on oilfield production. The key to effective treatment of asphaltene deposition is recognition of the problem. Asphaltenes can be identified and quantified using laboratory methods. In the past physical, mechanical and chemical treatments have been used to control asphaltene deposition in the oilfield. Chemical treatments have included aromatic solvents and low molecular weight dispersants. However, many of these treatments are ineffective. Recently, technically and economically effective methods to control asphaltene-created production problems have been developed. These applications make use of a new polymeric dispersant/inhibitor at clean-up dosages of 1,000 to 10,000 ppm and continuous dosages of 50 to 400 ppm. As a result of downhole clean-outs and chemical squeezes using the new dispersant/inhibitor, production increases have been achieved and maintained. Tank bottom and interface control has been achieved through continuous feed applications. In one case, an additional benefit of the treatment was increased effectiveness in demulsifying oil/water emulsions and maintaining cleaner discharge water.