Socio-spatial disparities are both a cause and a consequence of social inequalities. This thesis questions the role of social inequalities in the formation and correction of socio-spatial disparities. It is composed of three essays shedding light on different sides of this issue, involving residential migrations and public policies. The first essay analyses the relevance of the national strategic orientations of the rural development policy by the yardstick of the philosophical debate on social justice. It puts in evidence the role that play and should play the objective of reducing social inequalities in the definition of a policy acting on socio-spatial disparities. The two following essays show how social inequalities generate socio-spatial disparities through long and short distance residential moves. The second essay studies the effect of the feeling of aversion toward local inequality and of the income redistribution policy on interregional migrations and disparities, in the theoretical framework of the New Economic Geography. The last essay examines how social inequalities determine residential choices and produce socio-spatial segregation in the French urban areas, using econometric discrete choice models
