What Drawing on multi-level network theory, NetCareers suggests that social mobility is the product of individuals traversing complex interdependent networks. As people move in and out of organizations, they engage the networks of other people with equally complex histories, becoming part of the history of these organizations. From this vantage point, mapping social mobility becomes an arduous but also enriching analytical undertaking, requiring a more data-driven approach than what is commonly seen in social mobility research. New administrative datasets allow us to track cohorts through their entire school and workplace careers. NetCareers applies sequence analytic techniques and graphical probabilistic models to this data to identify variations and commonalities in career mobilities. Why Social mobility – the ability of individuals and groups to move in the social structure - is a cornerstone feature of modern societies, encouraging class equalizing investments in social welfare and education. In the Nordic countries, these investments have helped produce very high mobility rates: children from underprivileged backgrounds have gained access to more privileged positions. Mass education has been documented as the key driver behind these dynamics. Yet, social mobility is not solely a result of schooling; it unfolds through protracted careers. Today, we can observe the careers of those who grew up during the formative welfare state period. NetCareers contributes with new knowledge, characterizing the careers of individuals that rose from the bottom to the top. How NetCareers has the potential to leapfrog standard methodology in the field of social mobility studies specifically, and more generally to push how social scientists think about careers to take seriously the institutional complexities of actually lived trajectories. I am very grateful for the support of the Carlsberg Foundation in this regard. NetCareers assembles an inter-disciplinary team of researchers from the sciences and social sciences to develop new techniques for studying complex network careers. The team will draw on rich administrative data on the school and work careers of Danish children born in the 1960s and 1970s to explore new techniques that since will be replicated on similar data from other European countries. SSR Social mobility – the ability of individuals and groups to move in the social structure - is a cornerstone feature of modern societies, encouraging class equalizing investments in social welfare and education. NetCareers contributes with new knowledge about life course inequalities; identifying drivers in inequality of opportunity and outcome that are persistent to class equalizing institutions as well as processes that enable individuals and groups to escape the constraints that come with certain underprivileged positions.