: Urban planning is a very important issue to guarantee the sustainable development of modern towns. Many aspects must be considered and one of the most important is the population growth. Having a correct control of this phenomenon it is possible to focus the efforts, resources and investments in the right direction. To anticipate the facts and as a consequence predict the advantages and problems of the growth in a specific region this paper presents a web-based system for the simulation of the populations boom. The system uses a set of rules to predict the development in a given geographic scenario, focused on the needs for public resources such as schools, kinder gardens and public health centers. The outputs are SVG covering maps of the simulated region showing the suitability of the existing resources. Key words: Geographic Information Systems, urban growth, simulation, geographic scenario