1. PURPOSE OF PRESENT BOOK During the period May 19-26, 2003 the NATO Advanced Research Workshop (ARW) "Mud volcanism, Geodynamics and Seismicity" was held in Baku. Participants coming from USA, Germany, France, Italy, Portugal, Russian Federation, Ukraine, Romania, Georgia, UK, Israel, Azerbaijan, Tunisia have discussed about different geodynamic features of mud volcanism and participated to field trips oriented to a better knowledge of mud volcanic features. The Meeting focused on many features of mud volcanism occurrence and related geodynamic topics. The purpose of present book is to collect contributions discussed during the Meeting and to fill a marked editorial gap on mud volcanism. Mud volcanism was to date described by local monographies or by articles published by scientific journals. In particular no books were published on topics able to highlight the link among mud volcanism, geodynamics and seismicity. Mud volcano of Nirano (Northern Italy). Engraving from Stoppani A. (1871), Corso di Geologia, Milan, Bernardoni G. and Brigola G. Publishers. 2. WHY MUD VOLCANOES ARE GEOLOGICALLY IMPORTANT ? Mud volcanoes have attracted the attention of earth scientists for many years. Due to their importance in hydrocarbon research, a consistent progress in the knowledge of mud volcanism took place in the past twenty years. Mud extrusion is a well-known phenomenon occurring in geological environments where fluid-rich, fine grained sediments ascend within a lithologic succession due to their buoyancy.