This is an unprecedented, historical mapping of every decade of the 20th century and, from a publishing point of view, it is a triumph. By definition, the book has a global focus, but primarily covers Europe and the USA. With clear and measured prose, the reader is taken on a guided tour through the expansion and diversification of subject material by individual artists, forming carefully defined groups as well as individual representations. The long-standing shackles of 19th century art theory are energetically shaken off for painting and sculpture.

It is an extraordinarily difficult feat to take the year 1900, or for that matter, 2000, as a starting point for such progress: art theory does not respect thresholds. However, The Interpretation of Dreams, by Sigmund Freud, is as good a landmark as any and the visit of Matisse to Rodin's Paris studio, and his subsequent rejection of Rodin's sculptural style, make for a perfect starting point to the century. For the following decade, the editors have chosen to focus on the definition of Constructivism by the members of the Moscow Institute of Artistic Culture, as a logical practice responding to the demands of a new, collective society. Then follows the conjunction, in 1926, of El Lissitzky and Kurt Schwitters in showing work in Hanover - another key marker. The architecture of the museum as archive and the allegory of modernist space as a form of melancholia are noted as having been dialectically conceived by both Constructivism and Dadaism.

The commissioning of Charles Sheeler by the Ford Motor Company in the USA to document its River Rouge plant, is picked out as an inspirational landmark which encouraged North American modernists to develop, 'a lyrical relation to the machine age'. The publication in Britain, in 1937, of the Constructivist magazine Circle by Leslie Martin, Naum Gabo and Ben Nicholson also receives due merit. Two other key markers are Pierre Restany's organisation of the Nouveau Realisme group in Paris in 1960, and in 1962, Camilla Gray's The Russian Experiment in Art: 1863-1922 which revived western interest in the Constructivist principles of Vladimir Tatlin. This process of identifying major works of art history as catalysts is commendable, and recurs throughout the book.

The impression might be wrongfully gained that the book is predominantly theory-led, but this is not the case. Indeed, there are more 'incomplete projects' here than we may dare to admit, and particular themes, such as 'sublimation' and 'desublimation' are addressed incisively. The strong undertow of a continuing modernism and modernity emerges without diminution. Numerous intelligent and practical devices are used to bring even greater clarity to the main body of text, for example, the use of boxes related to specific subjects is admirably disposed and the general structure of text and content is woven together with great skill.

No review of this major source book should neglect to refer to the genesis of work in the ideas forum of October magazine. The October journals were edited by Annette Michelson, Rosalind Krauss, Douglas Crimp and Joan Copjec. October began in 1976 and, in the ensuing years, key articles by Rosalind Krauss, Yve-Alain Bois and Benjamin HD Buchloh were published. As the authors have said, they were 'continuing the unfinished project of the 1960s'. A key compendium, October, the First Decade 1976-1986, was duly published. If anything, October itself was a key critical landmark; but with commendable discretion, the four editors have chosen to play down this achievement. They, of course, were all there.

Art since 1900 is an essential library purchase and it could be said that no serious, contemporary historian can afford not to invest in this magnum opus. Indeed, the interaction of literature and film in the world of modernity suggests that numerous other literary authors and critics would be well advised to acquire a copy. The publishers, Thames & Hudson, (still a private, family company) are to be commended for their exceptional commitment to this work, in a world of conglomerates who would never have chanced their arm with such a project.

Michael Spens