A Decision Support System (DSS) at the national and international level for planning and assessment--its design and partial development--is the central theme of this paper. The paper also explains the organizational structure of a national agency needed to carry out the information projects that would give continuing support to such a system. The approach is new in that the design does not depend on the traditional set of elemental data elements, but just the contrary: the DSS lowest database elements consist of statistics and are aggregated at various levels. There are several sources of data, originated and collected by a great diversity of governmental, private, and international organizations. Even though the author acknowledges the high variety and magnitude of errors that are found in such sources, he literally maintains that to have an information system is better than having none at all. To build upon such data (aggregated, at that) will produce useless information for planning and assessment. Any run-of-the-mill statistician or computer scientist will spot at once the GIGO nature of the system. One good point about the paper is that it will give the reader a feeling for the magnitude and complexity of such a problem.