This book is the result of over three decades of deliberation by The International Union of Geological Sciences (IUGS) Subcommission on the Systematics of Igneous Rocks.

The Subcommission was originally set up after the International Geological Congress meeting in Prague in 1968 as the result of an earlier investigation into the problems of igneous rock classification that had been undertaken by Professor Albert Streckeisen from 1958 to 1967 (Streckeisen, 1967). He was appointed the first Chairman of the Subcommission, a position he held from 1969 to 1980 and was followed by Bruno Zanettin (1980–1984, Italy), Mike Le Bas (1984–2001, UK) and Bernard Bonin (2001–, France). The secretaries of the Subcommission have been V. Trommsdorff (1970–75, Switzerland), Rolf Schmid (1975–80, Switzerland), Giuliano Bellieni (1980–84, Italy) and Alan Woolley (1984–2001, UK).

During this time the Subcommission has held official meetings in Bern (1972), Montreal (1972), Grenoble (1975), Sydney (1976), Prague (1977), Padova (1979), Paris (1980), Cambridge (1981), Granada (1983), Moscow (1984), London (1985), Freiburg im Breisgau (1986), Copenhagen (1988), Washington D.C. (1989), Southampton (1996) and Prague (1999).

For these meetings the secretaries distributed 52 circulars to the members of the Subcommission containing a total of 164 contributions from petrologists throughout the world. All of these contributions have now been deposited in the Department of Mineralogy at the Natural History Museum in London and in the Library of the Geological Museum, University of Copenhagen.