The paper discusses controlling polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) emissions from incinerators by flue gas cleaning. New Source Performance Standards for municipal waste combustors (MWCs) and guidelines for existing incinerators in the U.S., proposed on December 20, 1989, are to be promulgated in December 1990. The proposed national regulations require more stringent control of particulate matter and include pre-combustion, combustion, and post-combustion controls, the last two depending on size and age of the facility. Dry scrubbing processes have been used exclusively on recent MWCs and are planned for future MWCs in the U.S. for flue gas cleaning (post-combustion control). They inherently include particulate matter control along with their primary function of acid gas removal. These technologies are also generally effective in controlling PCDDs, PCDFs, and trace heavy metals. Test results quantifying air pollutant emissions, especially PCDD/PCDF, and their control will be presented and compared with the proposed regulations.