Higher Education Institutions are undergoing important changes involving the development of new roles and missions, with implications for their structure. Governments and institutions are implementing strategies to ensure the proper performance of universities and several studies have investigated evaluation of universities through the development and use of indicator systems. In this paper, we review some of the systems applied to the OECD countries, with special attention to Spain. We demonstrate the difficulty involved in establishing classification criteria for existing indicators, on which there is currently no consensus.