From its creation in the 1990s, the Chilean monitoring and evaluation (M and E) system has represented a substantial part of the effort to improve the use of Chile's public resources within a broader context of multiple initiatives designed to modernize and improve public management in many areas. This close relationship with the budget has determined the primary characteristics of the M and E system, in both its design and operations. The M and E system's institutional coverage includes all the organizations in the executive branch of the central government and those included in the budget law for the public sector. The objective of this document is to give a broad view of the M and E systems in Chile, distinguishing the three stages and providing lessons for other countries that are developing their own systems. The first section focuses on the first period and its two stages: 1990-2000 and 2000-2010. These stages concentrate mainly on the role played by the budget office. The second period covers 2010-13, in which light is shed on both the new system's actors and the emphasis adopted by the authorities in charge, but at the same time the authorities largely continue and strengthen the existing tools from the M and E system of the previous period. The third section of the paper summarizes success factors and obstacles to success in the two periods. Section four states general conclusions regarding the main system's challenges and section five includes lessons for other countries.