The XXVI Scientific Meeting of the Argentine Association of Geophysicists and Geodesists was held in Tucuman, November 5-9, 2012. It included numerous contributions from representatives from the neighboring countries. The first issue of GEOACTA Volume 2014 is a Special Edition based on papers carefully selected from the scientific program. These thirteen articles from engineers and scientists in five countries were carefully selected to provide a review of recent developments in state-of-the-art techniques and methods of Engineering Geomatics and their applications to Earth Sciences in the South American continent.