This open access book is the first collection of chapters simultaneously addressing both the segmenting and the egalitarian function of individual labour law, in almost all countries of the world, between 1880 to the present . This collection of labour law and the leximetrics method is developing new forms of measurement of generosity and coverage in regulatory social policy. This is a groundbreaking contribution to regulative social policy research as it indicates both the relevance and the mechanisms of legal segmentation for labour market segmentation, unequal treatment and for social stratification with particular emphasis on the development in countries of the Global South. Its socio-legal approach fills gaps for sociological, legal and historical research of welfare states. It helps to understand the concept of legal segmentation from a theoretical, quantitative and qualitative perspective, and shows the potentialities of leximetric approaches to understanding segmentation of labour markets and society implied by regulatory social policy.