In line with the strategic recommendations of the Global Plan of Action for the Conservation and Sustainable Utilization of Plant Genetic Resources for Food and Agriculture approved at the Fourth International Technical Conference on Plant Genetic Resources (ITCPGR), Leipzig, Germany, June 1996 and of the Global Plan of Action on Food Security approved at the World Food Summit on Food Security (WFS), Rome, November 1996, the Andean countries of Latin America (LAC) face the need to strengthen the use of modern plant biotechnology for the conservation and sustainable agricultural use of genetic resources of under-utilized crops.  Advanced biotechnologies such as cell and tissue culture, molecular genome analysis, plant genetic transformation, molecular plant disease diagnosis and germplasm cryo-conservation can be successfully used to cope genetic erosion, to reinforce ex-situ collections and in-situ conservation, to upgrade the supply of improved and healthy seed and planting materials to farmers and to integrate a new approach into the development programmes for food production and food security in mountain lands.  Over the centuries more than 70 crops have been domesticated by the Andes inhabitants.  Presently, on 28 crop species, selected under the basis of adaptation to high altitude, agronomic use and yield, nutritional value and market potential, there are relative developments in terms of agronomic cultural management and scarce genetic conservation activities. ... The paper summarizes the main parameters and characteristics of 13 selected crops including the state of the art of plant biotechnology in the Andean countries and main applications and discusses perspectives and future impact of plant biotechnology for the conservation and development of food crops.