The large-scale introduction of computers in general secondary schools during the 1980s has resulted mainly in a focus on teaching students how to use computers. The current wave of thinking however is to emphasize more the integration of computers into the general learning experience, that is the use of computers as educational tools. For monitoring the complex process of integrating computers in education and for studying changes over time, indicators are needed. This article examines the quality of some indicators for measuring the integration of computers in education. Data from the IEA world-wide survey on `Computers in Education¿ were used to construct such indicators. The results show that a very general rating by principals of the ways computers are used in a school can serve as a reliable and valid indicator of the degree of computer integration in schools.