This volume describes the wide-ranging scientific activities of Leon Van Hove, through commentaries by his colleagues and a selection of his most influential papers and documents. The reprinted papers are grouped by topic, and there is a selection of his speeches and thoughts on science.

Part 1: selected papers on lattice dynamics and neutron scattering, commentary by N. Gidopoulos and S.W. Lovesey; selected papers on perturbation theory of large quantum systems, commentary by N.M. Hugenholtz, and on an extension of the Lee-model, commentary by Th.W. Ruijgrok; selected papers on equilibrium statistical mechanics, commentary by R. Balescu and I. Prigogine, and on non-equilibrium statistical mechanics, commentary by T. Petrosky and I. Prigogine; from neutrons to quarks, J.J.J. Kokkedee; selected papers on longitudinal phase space analysis, commentary by W. Kittel; selected papers on high energy collisions and internal hadron structure, commentary by A. Bialas; selected papers on ultrarelativistic heavy ion collisions, commentary by M. Jacob; selected papers on multihadron production and QCD parton showers, commentary by A. Giovannini; from particles to stars to astroparticles, commentary by G. Setti. Part 2: Leon Van Hove in Utrecht, N.M. Hugenholtz and Th.W. Ruijgrok; Leon Van Hove at CERN, F. Bonaudi, M. Jacob, E. Gabathuler and V. Soergel; Leon Van Hove at Max-Planck-Institut in Munich, N. Schmitz; Leon Van Hove at the European Space Agency, R.M. Bonnet. Part 3: the man in his own words, M. Van Hove.