At the thirty-third session of the Economic Commission for Latin America and the Caribbean (ECLAC), which was held in Brasilia in 2010, member States adopted a resolution entrusting the secretariat with a new mandate to continue to analyse, in collaboration with other international and regional intergovernmental agencies, new alternatives for generating the volume of resources necessary for financing the development of the countries of Latin America and the Caribbean; and develop, in collaboration with other international and regional agencies, a broader set of indicators to reflect the particular realities in the countries and support the identification of their main needs, so that classification as a middle-income country ceases to be an a priori impediment to participation in official development assistance. In compliance with this mandate, the ECLAC secretariat has prepared this report, which argues that constraints and challenges associated with development must not be treated as related in a linear fashion to countries' per capita income levels. The document proposes fine-tuning the approach and complementing the per capita income criterion with a new perspective that addresses the structural gaps that constrain the development of middle-income countries, in terms of inequality and poverty, investment and saving, productivity and innovation, infrastructure, education, health, fiscality, gender and the environment. This calls for a review of the concept of development used to channel cooperation resources, and the adoption of a broader, multifaceted view which entails not just improving people's standards of living but also achieving sustainable and inclusive growth, whereby the problems of social inequality and productive heterogeneity characteristic of Latin American and Caribbean countries and middle-income countries as a whole can be addressed.