Cross-sector social collaborations are increasingly recognised as valuable inter-organizational arrangements that seek to combine the commercial capabilities of private sector companies with the deep knowledge of social and environmental issues enrooted in social sector organizations. In this paper we empirically examine the configurations of conditions that lead to lasting cross-sector social collaboration. Situating our enquiry in Schütz’s theory of life-worlds and the reciprocity literature, we employ fuzzy-set qualitative comparative analysis (fsQCA) to analyse data gathered from 60 partners in 30 cross-sector social collaborations. We find two distinct types of configurational pathways leading to lasting cross-sector social collaboration which we label reciprocal economic exchange based on direct reciprocity, and reciprocal social exchange based on generalised reciprocity. The pathways vary in terms of the delivery of expected and unexpected resources and benefits. We introduce the concept of double relationality to explain the interdependence of structure and action in lasting cross sector social collaboration.