The 18th International Senckenberg Conference (VI International Palaeontological Colloquium in Weimar) "Late Neogene and Quaternary biodiversity and evolution: Regional developments and interregional correlations" was hosted by the Senckenberg Society, Research Unit of Quaternary Palaeontology Weimar on April 25 to 30, 2004. This conference was dedicated to Hans-Dietrich Kahlke, one of the senior distinguished leaders of interdisciplinary Quaternary palaeontological research in Eurasia. 165 participants from 28 countries presented current topics and results of their research on the evolutionary history of European, Asian, African and American Late Neogene and Quaternary floras and faunas. Scientific problems from the whole northern hemisphere as well as from key regions of the southern hemisphere were discussed. The conclusions of the conference are included in two special proceedings volumes. This is the first of the two volumes. It starts with H. Hemmer's biographic sketch of Hans-Dietrich Kahlke, followed by 24 papers containing results on the evolution, systematics and palaeoecology of groups of mammals in taxonomic order, with contributions by G. van den Bergh, M. Bukshianidze, E. Cregut-Bonnoure, R. Croitor, T. Deng, M. Dermitzakis, V. Eisenmann, H. van Essen, A. van der Geer, F. Lacombat, G. Lyras, J. van der Made, F. Marcolini, R. A. Martin, C. Najdeck, R. Sardella, A. Siefker, M. Sotnikova, L. M. Takken Beijersbergen, A. Vekua and J. de Vos. Regional studies follow, approximately in stratigraphical order, with contributions by L. Abbazzi, M. T. Alberdi, J. Argant, L. Bishop, B. Blackwell, A. David, E. Debard, E. Delson, S. Elton, M. Faure., J. L. Franzen, A. Garapich, C. Giovinazzo, C. Guerin, W. Harcourt-Smith, L. van den Hoek Ostende, N. Hudackova, V. Konecny, D. S. Kostopoulos, A. Lamb, M. Marchetti, E. Martin-Suarez, F. Masini, P. P. A. Mazza, J. Miroslaw-Grabowska, A. Monguillon, A. Nadachowski, T. Obada, H. O'Regan, M. R. Palombo, F. Parenti, V. Pascaru, J.-F. Pastre, M. Sabol, B. Sala, S. Sen, A. R. Skinner, M. Slamkova, N. Spassov, C. C. Swisher III, Z. Szyndlar, T. Tomek, I. Tunyi, A. Turner, A. M. F. Valli, D. Vass and I. Vislobokova.