ABSTRACT The 1993 World Development Report, Investing in Health, suggests policies to assist governments of developing countries in improving the health of their populations. A new methodology to improve government spending is introduced. Epidemiological and economic analyses from the basis for a global priority setting exercise, leading to a recommended essential public health and clinical services package for low- and middle-income countries. Ministries of Health in many countries have expressed an interest in designing a national package of essential health services, using the methodology. Given the apparent importance attached to the study and its far reaching potential consequences, this article provides an overview of the method, the main issues and problems in estimating the burden of disease as well as the cost-effectiveness of interventions. Strengths and weaknesses in the databases, value judgements and assumptions are identified, leading to a critical analysis of the validity of the priority setting exercise on the global level.