Transnational education (TNE) has emerged as a pivotal modality in the globalisation of higher education, enabling institutions to extend their academic reach across national borders through diverse collaborative arrangements. This chapter examines the strategic, operational, and relational dimensions of building sustainable TNE alliances. Drawing on partnership theory, institutional trust frameworks, and empirical evidence from journal-based scholarship, the chapter proposes a comprehensive 'Partnership Playbook' that guides institutions through the stages of partner selection, governance design, quality assurance, cultural integration, financial modelling, and long-term sustainability planning. It argues that durable TNE alliances are not merely contractual arrangements but deeply embedded relational systems requiring continuous alignment of values, expectations, and institutional capabilities. The chapter concludes with forward-looking recommendations for policy and practice.