The Fray International Symposium on Metals and Materials Processing in a Clean Environment was held in Cancun, Mexico from November 27th to December 1st, 2011 at the Fiesta Americana de Condesa Resort. It was organized in honor of the distinguished work and lifetime achievements of Dr. Derek J. Fray, a well known figure for his deep impact in materials extraction and processing world, especially for developing sustainable new technologies. Prof. Fray is author of almost 400 scientific papers and inventor on approximately 179 patents arising from 62 families of patents. He is Fellow of some of the most prestigious professional societies around the world. Throughout his career his activity has impacted various fields such as non-ferrous, ferrous and nano-scale materials processing; many processing routes including pyrometallurgy, hydrometallurgy, chemical vapor synthesis and processing, recycling; and several investigation techniques such as experimental measurements and physical modeling and simulation.