This session is part of the mini-symposium on "The Future of the Social Investment State". There is still limited empirical knowledge about how social investment is implemented in different national contexts. This session of the mini-symposium includes contributions that take stock of the development and implementation of social investment policies across Europe. It looks at how to contextualize social investment reforms and assess their ‘return’ rates and potential pitfalls. Social investment should foster labour market inclusion, fight social exclusion, and develop human capital throughout the life-course, thereby mitigating inequalities in the long-term. So far, however, there is mixed empirical evidence about whether social investment policies have been able to achieve these goals. Research in several policy areas (child care, active labour market policies, education) has shown that, rather than achieving its progressive and redistributive goals, social investment policies might create or reinforce “Matthew Effect” patters, with higher socio-economic strata benefitting more from them than other groups of the population. However, these “Matthew Effect” have not the same strength and effects in all countries and there are many cases where social investment policies are not matched by severe “Matthew Effects” and “inclusive growth” has been achieved or is achievable.Therefore, the session provides an empirically based, more nuanced and encompassing analysis on the link between social investment, “inclusive growth” and inequality.