A project promoting the exchange of information on polychlorinated dibenzo-p-dioxins and related chemicals has been initiated on an international basis by the North Atlantic Treaty Organization (NATO). Information being exchanged concerns research and other activities which involve polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and related chemicals. In addition to the major information exchange objective, secondary objectives include the reduction of research program duplication and the assistance in identification of knowledge voids. NATO-member countries participating are Canada, Denmark, the Federal Republic of Germany, Italy, the Netherlands, Norway, the United Kingdom, and the United States. The project is divided up into three basic working groups: (1) exposure and hazard assessment, (2) technology assessment, (3) management of accidents.