LAUSR

Abstract Nowadays, many wicked problems such as environmental issues require organizations from multiple sectors to form cross-sectoral alliances. Cross-sectoral alliance networks can transfer resources and signal affiliations and value alignment between strategic partners. The communication of cross-sectoral alliances is a form of CSR communication that serves organizations’ strategic goals and objectives. Drawing on the literature on digital CSR communication and legitimacy theory, this article examines which legitimacy needs shape the formation of cross-sectoral ties on Facebook in addressing environmental and sustainable development issues in the United States. Combining data-mining, text-mining, social network analysis, and exponential graph modeling, this research investigates the structure of a network among 3071 organizations across multiple sectors. Findings show that organizations’ cross-sectoral tie formation is mainly driven by social legitimacy and alliance legitimacy needs.