This research project, in conjunction with the SIMLII foundation's 80th anniversary, is aimed to reconstruct the historical chronology of the institutional life of the Society: the Directive bodies, the by-laws, the main steps of the scientific activity, especially the Congresses of Occupational Health. The research will also analyze the most important elements of historical context explaining Society's evolution: the relationships between SIMLII and political-institutional and legislative framework, social and economic changes, medical science's evolution and the university teaching and research, and finally the interactions with the international context. The research covers the years since the first national meeting of Occupation Health, in 1907, in which scientific activity was particularly intense, although the foundation was officially only in 1929. The investigation of the documentation after the 2nd World War is aimed at reconstructing the reborn of the international relations and the social, cultural and economic changes occurred between 1968 and 1978 and the deep impact on industrial relations and the enactment of the "Statuto dei lavoratori" in 1970 and the Health Reform in 1978.