PIP: This paper has 3 main objectives: 1) to describe the methods most used for the projection of urban-rural population; 2) to present some basic problems and the manner in which to solve them (comparison of definitions used in the sources), as well as the way to determine the initial population; and 3) to examine these 2 methods, the components method and the U.N. method, in some detail. The description of methods is made and includes, in some cases, the optimum way for them to be utilized. In the case of the initial population, specifications are given as to how to determine it, stressing the importance of counting on uniform definitions of urban population. The components method is analyzed mainly with regard to the type of information necessary for its application, pointing out the different possibilities for the determination of variables. Insofar as the U.N. method is concerned, the basic assumptions are analyzed and the main analytical relationships are deduced, indicating the way in which to apply it as well. (author's)