Over the last few years, environmental concerns have led to the emergence of the integrated management of pest and pesticides (IMPP) as a new way to deal with pests and pesticides in agriculture. Although the environmental and economic benefits of IMPP are beyond doubt, its use has been somewhat limited. One reason is the sheer amount of knowledge required of such things as climate, topography, soil type of the farm, agronomic practices, crop phenology, biology and damage potential of the pests and options available for suppressing their population below the economic injury levels. Unfortunately, such knowledge typically resides within a few experts and is not easily available to farmers. In order to make this knowledge more widely available, we developed CPEST, an expert system for managing pest and diseases of coffee in a developing country. The paper describes the architecture and development of CPEST, gives examples of the interface that a farmer would use to enter information and provides an evaluation of the quality of the advice that CPEST provides.