The paper reports on a study to evaluate organic combustion by-product emissions while feeding varying amounts of bromine (Br) and chlorine (Cl) into a pilot-scale incinerator burning surrogate waste materials. NOTE: Adding brominated organic compounds to a pilot-scale incinerator burning chlorinated waste has been found to enhance emissions of volatile and semivolatile organic chlorinated products of incomplete combustion (PICs) including polychorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs). This phenomenon appears to be sensitive to temperature and combustion conditions. The surrogate waste was fed at a constant molar halogen input rate, with varying Br/Cl molar ratios. An increase in the total PCDD/F concentration due to the addition of Br was not observed consistently. PCDD/F homologue distribution shifted toward the higher chlorinated species. Perhalogenated or nearly perhalogenated mixed Br/Cl dioxins and furans were also observed.