Prof. Ian S. Williams is a Professor Emeritus at the Research School of Earth Sciences, Australian National University, Canberra, Australia. He has published more than 487 papers and written many books. His research interests include the micro-scale behavior of mineral isotopic systems under diverse geological conditions; the age, origin, and thermal history of Earth's crust with a particular emphasis on the early Earth, granite gneiss, polymetamorphic terranes, and sediment provenance; paleoclimate; and instrumentations and techniques for ion microprobe analysis of geological and biological minerals.