Industrialization and development increase the demand for information. Specialization of functions and organization also greatly increases the need for coordination and thus the social returns to and demand for information. Agricultural information systems are useful to 1) the government officials dealing with food policy and agriculture, including the central bankers, and enterprises in the public sector; 2) the private sector; and 3) the donors and international organizations. The basic focus of this paper is to review the state of knowledge about the process of improving agricultural market information for both private and public sector uses in developing countries. This involves the question of whether it is wise to invest resources in information services rather than in alternatives like infrastructures. The aim is the improvement of the market coordination of existing firms in the food system. This paper will bring the attention of government officials and rural development personnel to the collection, analysis and dissemination of agricultural information.