Asphaltene deposition during production of crude oil is costly and troublesome. Asphaltene can be deposited in any area of an oil-production facility but most damage occurs in the near-wellbore area and inside the electrical submersible pump (ESP). Heavy-organics deposition from asphaltene flocculation can be controlled through better knowledge of mechanisms that cause deposition. Crude oils,vith high resin and maltene content are more stable. Changes in temperature, pressure drop, and electrokinetic effect caused by a buildup of electrical-potential difference along the conduit can influence the thermodynamic equilibrium of oil and cause asphaltene deposition. Early diagnosis of the crude-oil tendency to precipitate asphaltenes and prevention of these deposits may seem costly at first but may increase considerably after deposition occurs. In severe cases, continued economical production may not be possible. New methods to prevent asphaltene deposition in ESP equipment include use of variable-speed controllers (VSC＇s) combined with oversized pumps operating at lower speed, increased impeller-vein height, internal pump coatings, reduced pressure drop at the pump intake by use of new screen styles, and new intake designs. The use of an injection capillary line and fluid recirculation enhances chemical treatments.