© 2019, © 2019 Oxford Department of International Development. This paper examines the consequences of the hugely successful expansion of South-South Cooperation since the new millennium. For all the achievements, variations and change over the 1950s-late 1990s, ‘SSC 1.0’ was characterised by relative neglect within the 'international' development community, and by many orthodox and critical scholars. In the chronological schema of the paper, ‘SSC 2.0’ refers to the period of remarkable expansion from the early 2000s to the present. The emergence of ‘SSC 3.0’, I suggest, is currently revealed by a discernible set of shifts driven in large part by the expansionary successes of SSC 2.0, as well as other turns in the global political economy. Three contemporary trends are identified: cooperation narratives that are increasingly ‘muscular’, nationalistic and pragmatic; difficulties sustaining claims to ‘non-interference’ in partner countries; and the further erosion of ideational and operational distinctiveness.