Exhibition catalogue published in conjunction with show held at Stadtisches Museum, Leverkusen, October - November 1969. Introduction by Rolf Wedewer. Includes texts by the artists. Edited by Konrad Fischer and Rolf Wedewer. Cover design by Sol LeWitt. Exhibition included Keith Arnatt, John Baldessari, Robert Barry, Iain Baxter, Bernd & Hilla Becher, Mel Bochner, Alighiero Boetti, Marcel Broodthaers, Stanley Brouwn, Daniel Buren, Victor Burgin, Donald Burgy, Eugenia Butler, Pier Paolo Calzolari, Paul Cotton, Hanne Darboven, Jan Dibbets, Hamish Fulton, Gilbert & George, Dan Graham, Douglas Huebler, Richard Jackson, Stephen Kaltenbach, On Kawara, Michael Kirby, Joseph Kosuth, David Lamelas, Sol LeWitt, Bruce McLean, Bruce Nauman, Giuseppe Penone, Adrian Piper, Sigmar Polke, Emilio Prini, Markus Raetz, Alan Ruppersberg Ed Ruscha, Fred Sandback, Richard Sladden, Robert Smithson, Timm Ulrichs, Bernar Venet, Lawrence Weiner, Zaj / Walther Marchetti. Includes exhibition history for each artist. Illustrated in black-and-white. Text in German and English.