In Belgium, life expectancy is now twice what it was 170 years ago due to improvements in public and private hygiene, nutrition, medical procedures and the organization of health services. The average lifespan of a Belgian resident is now over 80 years, but inequalities persist and sometimes even intensify. In Belgium, like in other European countries, a negative relationship has been demonstrated between socio-economic position on the one hand and health and mortality on the other hand. This project aimed to investigate whether or not this social gradient in health and mortality is associated with the growing de-standardisation of employment arrangements and family situations. The goal was to obtain information about the mechanisms by which social differences in mortality and health are generated in Belgium, in order to provide insight in policy measures that could prove effective in countering these inequalities. In a first part of the project, the evolution of mortality inequalities in Belgium between 1991 and 2016 was studied. It has been shown, based on a multidimensional indicator combining educational level, employment category and housing characteristics, that social inequalities in death are significant in Belgium and that they have been increasing for both women and men since at least the 1990s. In relative terms, gaps between social groups are especially wide between 25 and 50 years but have little impact on differences in life expectancy because the risk of dying is inherently low at these ages. The social disparities in mortality for older people (65+) – and especially the delay of the underprivileged in the health transition and the fight against cardiovascular diseases – have a far greater effect on differences in life expectancy. In general, social inequalities in mortality and their variation along the social continuum are observed for each of the major causes of death, but they are particularly pronounced for diseases of the respiratory and circulatory systems. The results also point out ...