Trustees span the boundaries between universities and their environments, and therefore may connect universities to other organizations. We use social networks and latent profile analyses to chart changes in the affiliations that trustees of AAU member universities maintained with other organizations from 1975 through 2015. Results identify a well-established hierarchy of connectivity across elite universities. We also chart change in profile membership over time. We observe decline in connectivity from 1975 to 1995, followed by a period of resettlement characterized by a steepened hierarchy of affiliations and a growing number of very highly connected boards. Evidence suggests that boards at the top of the connectivity hierarchy differ systematically from those with fewer affiliations. By 2015, very highly connected boards generally oversaw well-resourced private universities. A few public boards were once very highly connected, but this became less common over time. These results suggest important implications for future research on the relationship between governance and institutions' financial positions.