In this monograph all the worldwide known data of pre-Carboniferous units of the San Rafael block are compiled; these include petrography, geochemistry, isotope geochemistry and geochronology. This compilation represents an extensive database to be consulted by and in the interest of a broad scientific community. For many years, scientists around the world have been interested in understanding the evolution of Gondwana and its interaction to Laurentia. The southern Pacific South America proto-Andean Gondwana margin is characterized during the Paleozoic by the presence of orogenic belts accreted to the cratonic areas. The San Rafael Block, located in the south-central part of the Mendoza Province, Argentina is part of one of these terranes (Cuyania). It is composed of isolated outcrops of pre- Carboniferous units (Mesoproterozoic to Devonian in age), Upper Paleozoic sedimentary and volcaniclastic rocks, Permian-Triassic volcaniclastic and magmatic complexes and Cenozoic volcanism. In the present monograph all the worldwide known data of pre-Carboniferous units of the San Rafael block are compiled; these include petrography, geochemistry, isotope geochemistry and geochronology.