Purpose: The purpose of this study is to map and analyze sustainability activities and relationships at the seven Claremont Colleges and graduate institutions using social network analysis (SNA) to inform sustainability planning and programming. Design/methodology/approach: Online surveys and interviews were conducted among faculty, staff and students, and a network map was created and analyzed using network statistics to identify network characteristics. Findings: The mapped sustainability network has 291 one- and bi-directional connections but with substantial differences among institutions. Pomona and Pitzer colleges have the highest number of sustainability-related courses because of their popular Environmental Analysis programs. The two graduate schools and Scripps College are comparatively isolated. Scripps' network is small but highly interconnected and resilient. Pomona's network is extensive but concentrated on a single node. Several other key actors were identified based on the number of nodes extending from or connecting to them. Several new sustainability initiatives were recently launched in response to the study. Practical implications: SNA and mapping for campus sustainability can highlight network gaps and network vulnerabilities. To increase completeness, a representative and sufficiently large data sample is needed, requiring multiple, coordinated forms of contact. Interviews yield more detailed and comprehensive information than online surveys but are more time-consuming. Thus, the combination of electronic surveys and in-person interviews can be a successful strategy for maximizing information collection. Originality/value: The case study was the first of its kind conducted at the Claremont Colleges and one of the first in higher education. It informs sustainability planning, coordination and integration efforts.