The upward revision of population estimates and recent changes in retirement legislation raise questions about the future level of labour resources in mainland France and their composition. A basic and partial answer is provided by the trend-based projection for the labour force, continuing the trends observed in working life, fertility, mortality and migration, without the influence of cyclical variations. The growth in the workforce will gradually slow until 2015; then it will remain steady at between 28.2 and 28.5 million. Gains in activity will come from the more widespread practice of women and senior citizens working - they will be employed more frequently because of having spent longer in the education system and new retirement legislation. Nevertheless, due to growth in the elderly population, in 2050 there will only be 1.4 working persons for every non-working person over 60, compared with 2.2 in 2005. Alternative scenarios coexist with this trend-based projection, which allow us to calculate the size of the deviation to which demographic changes or different working patterns could lead. Different assumptions about net migration would have an immediate effect on the working population, whilst rising or falling fertility would not have an effect until after 2025. However, all the variations in the workforce or demographic behaviour which have been considered would only have a minimal impact on the ratio of working people to non-working over 60s.