This article explores how sustainable international partnerships in higher education might be constructed by linking the strategic and contingent through interpersonal relationships. It aims to foreground the role of individuals in developing and sustaining international partnerships amid an increasingly strategic landscape of higher education internationalization. To present how individuals themselves make sense of their efforts in building sustainable international partnerships in higher education across different contexts, 31 semi-structured interviews were conducted with different administrative and disciplinary staff in two universities in the United Kingdom and China. Findings suggest that interpersonal relationships provide a strong basis for sustainable partnerships and it is through contingent networking between individual academics that interpersonal relationships are developed. However, it is through strategic planning by senior academics that interpersonal relationships are embedded in the institution. Hence, an approach to linking the strategic and contingent through interpersonal relationships is thus proposed to build sustainable international partnerships.