Carbon black has historically been used in electrophotographic toners as a black pigment. Its properties influence some of the key performance attributes of the toner, including the printed image density and the toner's electrical characteristics. In the last decade demand for higher resolution and lower cost printing has driven significant improvements in toner performance. These changes have shifted the production of new toners from the conventional pulverization process to more complex chemical processes. In these new processes, carbon black and the other pigments are typically first dispersed into a liquid matrix (aqueous or organic solvent or monomer) and are then incorporated into the toner particle either by chemical assembly processes, such as emulsion aggregation, or direct polymerization. Throughout the various process steps the carbon black needs to remain dispersed in the matrix to optimize the performance.Cabot has developed surface modification technology that allows the design of the carbon black surface chemistry to match the properties of its surrounding matrix. In this presentation we will explore the sensitivity of the carbon black dispersion quality to changes in the polymer properties. We will also demonstrate how careful control of the surface chemistry can enhance the dispersion of the carbon black.