Professor emeritus, MD PhD, Copenhagen University, Denmark and Fundacao Oswaldo Cruz, Brazil. Finn Diderichsen has been teaching social medicine and social epidemiology at Karolinska Institutet and at the University of Copenhagen. His research has focused on determination of social inequalities in health and policies to tackle them. Currently, he is adjunct professor at Oswaldo Cruz Foundation in Brazil. fidi@sund.ku.dk ABSTRACT Social investment policy has become a central response to the demographic and economic challenges facing European welfare states. This focus on investment in human capabilities and their efficient use is, however, challenged by health inequalities where education, health and employment are increasingly linked. This paper outlines the main principles of social investment policies (learning, activation and protection) and links them to a conceptual model of health inequalities and the policy entry-points tackling them by addressing the processes of social stratification, differential exposure and vulnerability as well as differential consequences of illness. It illustrates, with reference to selected empirical studies from the Nordic countries, how the balance between the elements of social investment policies might be adjusted, resources allocated differently and policies supplemented by more direct investments in health so as to enable social investments to tackle the health divide.