Mexico is a megadiverse country, which is home to a number of endangered and critically endangered species, the populations of some of which have been reduced to a few hundreds of individuals as the result of a range of pressures including land use change, habitat and ecosystem fragmentation, invasive species, overexploitation of natural resources and pollution. To address this problem, SEMARNAT, through CONANP, established the Programme for the Conservation of Endangered Species (PROCER), covering the period 2007-2012. PROCER recognises that the continued existence of these species is highly dependent on the existence of effectively managed protected areas in their remaining areas of natural distribution. As now framed, however, the PA system excludes critical habitats for these endangered species; second, PAs are too small to sustain populations of some endangered species, which move between PAs and unprotected habitats, meaning that there is a need to secure corridors and seasonal dispersal areas; and third, there is a need to strengthen threat managementÔÇöincluding through better enforcement. The solution to this situation will involve a strategic expansion in the PA system; management of critical habitats in the landscape as buffer areas by instituting a stewardship framework; engaging stakeholdersÔÇöprivate sector and communities to engage in stewardship, and developing incentives to encourage stewardship. This project will build on the achievements of PROCER, ensuring that instruments and capacities are established that will ensure the effective and sustainable functioning of these PAs with regards to the conservation of priority endangered species. Key aspects on which it will focus, in order to achieve this effectiveness and sustainability, are i) an ecosystem and landscape-wide approach to PA design, planning and management; ii) the involvement of local communities in the management of endangered species and their habitat; and iii) financial sustainability.