Summary: This paper presents a data envelopment analysis model that can be implemented by public sector management for assessing the efficiency of a health system within a developing country. To illustrate the practical implementation and interpretation of the model this study compares health systems across 51 developing countries using 1998–99 data. The results of the analysis generated empirical indicators of efficiency, and we demonstrate how these may then be used by management in order to understand the factors associated with good performance of a health system.