This paper argues that evaluations of basic research are best carried out using a range of indicators. After setting out the reasons why assessments of government-funded basic research are increasingly needed, we examine the multi-dimensional nature of basic research. This is followed by a conceptual analysis of what the different indicators of basic research actually measure. Having discussed the limitations of various indicators, we describe the method of converging partial indicators used in several SPRU evaluations. Yet although most of those who now use science indicators would agree that a combination of indicators is desirable, analysis of a sample of Scientometrics articles suggests that in practice many continue to use just one or two indicators. The paper also reports the results of a survey of academic researchers. They, too, are strongly in favour of research evaluations being based on multiple indicators combined with peer review. The paper ends with a discussion as to why multiple indicators are not used more frequently.