This conceptual article discusses the issue of friendship implied by the term "critical friends". Our argument relates to the generalized use of the term "friendship" and the assumptions that it may carry compared with the actuality of the roles played by critical friends. We attempt to build a more precise definition of friendship which we believe can clarify what critical friends might be which is different from the utilitarian notion between critical friends. The article draws on Aristotle's work to develop a contemporary taxonomy of forms of friendly relationships and discusses this in the context of school improvement. (Contains 2 tables.)