The Report of the Secretary General of the United Nations on the implementation of the Millennium Declaration, entitled In larger freedom: towards security, development and human rights for all" is a strong reminder of the need for an integrated approach to the various subjects considered therein, specially as they relate to the consolidation of democracy and of a durable peace. The subsequent establishment of the United Nations Peacebuilding Commission, has opened a promising instance for the contribution from different sectors to the fundamental task of post-conflict reconstruction. This process is clearly linked to the efforts dealing with conflict prevention, since one of the challenges of peacebuilding is precisely to face those deep root causes of the original conflicts whose reiteration could turn into the seed of a new conflict in the long term. It seems that UN components responsible for development issues could contribute to identify the economic and social causes which gave raise to the original conflict, and to put forward some strategies to revert them, specially focusing on the need to transit from humanitarian assistance to development. The present documents concentrates on the analysis of the post conflict reconstruction processes in three countries (Bosnia and Herzegovina, El Salvador and Sierra Leona), identifying similarities and differences and given special consideration to education and health issues. It is expected that the paper may represent a contribution to the work of the Peacebuilding Commission, in the framework of the cooperation of this body with the Economic Commission for Latin America and the Caribbean (ECLAC)."