This article is based on sessions at AUA Conferences in 2006 and 2007, which looked at some factors to take into account when considering the structure of the administration. Roughly, "administration" is defined as the "non-academic" management and operations that support the delivery of teaching and learning, research, and enterprise--in old money, everything that the Secretary, Registrar, Bursar and Librarian would have been responsible for; in new money, the Professional and Academic Services--while "structure" is defined as the organisational units and roles in the institution, and the relationships between them in terms of reporting lines and career paths. In this article, the author describes some models presented to and validated by delegates at the Conference sessions, along with some of the advantages and disadvantages that were described. He also presents some general principles which can be derived and applied to determine which model best fits a specific institution. (Contains 2 figures.)