This meeting is intended to bring together the participants of the IAEA CRP "Radiochemical, chemical and physical characterization of radioactive particles in the environment". Some of the collaborating CRP laboratories will be from Denmark, Finland, Germany, Hungary, Israel, Kazakhstan, Norway, Russia, Spain, Ukraine, and USA. The goals of the meeting are the following: - to exchange information about the results of the ongoing research; - to recommend harmonized analytical methodologies for physico-chemical characterization of "hot particles"; - to identify and recommend best approaches for investigating environmental impact of particle associated radionuclides; - to present the work plans for the forthcoming year. Participants will have the opportunity to present an "Invited Lecture" on recent activities related to the CRP carried out at their home institutes.