Collectively, its 25 members enrol over 1.3 million students and employ over 220,000 staff and faculty. Their collective budgets amount to over US$25bn and they have an annual research grant income of over US$6.5bn.

All Universitas 21 member institutions are research-led, comprehensive universities providing a strong quality assurance framework to the network's activities.

The network's purpose is to facilitate collaboration and cooperation between the member universities and to create opportunities for them on a scale that none of them would be able to achieve operating independently or through traditional bilateral alliances.

The University of Edinburgh was a founder member of U21 and participates in a number of its activities.