Although high-styrene resins have become of great commercial importance during the past 5 years (approximately 25,000,000 pounds manufactured in 1949), comparatively little information on the polymerization processes or any systematic review of their properties can be found in the technical literature. The object of the present paper is to supply such information. A series of butadiene-styrene copolymers with charging ratios of 50/50, 40/60, 30/70, 20/80, and 10/90 was prepared. Polystyrene, prepared under the same conditions, was included as a control. Properties of the latexes and resins obtained, presented in a systematic manner, were found to be largely dependent on the monomer ratio employed in the polymerization. for the first time a coherent picture is presented of the entire plastic range of the styrene-butadiene resins. This should encourage the further development of this large and expanding field, which includes such applications as natural and synthetic rubber reinforcing, impact resistant compositions, protective coatings, and latex paints.