The Cosmop program involves establishing a cohort for the systematic monitoring of mortality by occupation and economic sector in the general population. This descriptive study drew on the Permanent Demographic Sample (PDS), representing approximately 1% of the French population, established by INSEE in 1968 and updated over time with sociodemographic and occupational data from vital records and census reports. The cause of 97% of the observed deaths was identified. Relative risks (RR) of death were systematically calculated by cause for each sector of activity compared to other sectors. Overall mortality and mortality by cause of death among the 137,860 men (35,968 deaths) and 105,290 women (13,797 deaths) who had a known occupational status during the study period and were included after data validation are presented. A rather marked relative excess mortality is observed in the industrial and manufacturing sectors, while relative undermortality is observed in the agricultural sector and in certain sectors of trade and services. This study provides, for the first time, mortality indicators by cause and by occupational sector for the entire French population. (R.A.)