This volume collects the invited lectures and contributed talks of the NATO Advanced Studies Institute (ASI) held in Kemer/Turkey, from 22nd September to 2 October 2003. The meeting brought together experts from several fields in nuclear physics in which rapid progress has been made in recent years.
Ultrarelativistic heavy ion collisions have been investigated at CERN and at the Relativistic Heavy Ion Collider (RHIC). Several talks review the present status of experiments and develop the theory of nuclear reactions at ultrarelativistic collisions energies. The properties of hot and dense hadronic matter are studied and the predictions of Quantum Chromodynamics (QCD) for quark deconfinement and the phase transition to the Quark Gluon Plasma are described. The dynamical description of phase transitions in small systems and the methods of nonequilibrium many body theory are covered by several speakers. Furthermore the available information on the nuclear equation of state, the properties of cold dense quark matter, and colour superconductivity are presented in this volume. The close connection of these questions with astrophysics is drawn in several contributions related to the structure of stars, the dark matter problem, and the early universe. A second focal point of the ASI, besides highly energetic heavy ion collisions, is the physics of exotic nuclei far off stability and superheavy elements. Several leading experts in this field discuss the structure, the decay modes and lifetimes of superheavy nuclei both from the theoretical and the experimental points of view. Additional topics are the description of fusion and fission processes, the properties of halo nuclei and nucleibeyond the line of particle stability.

Ladies and gentlemen, dear colleagues, welcome to Kemer to the NATO Advanced Study Institute Structure and Dynamics of Elementary Matter. We have chosen Kemer as the place of our NASI because it is located in a be- tiful and hospitable surrounding. This part of the Mediterranean at the Turkish Riviera is a historic region where many cultures meet (e.g., the Oriental and the Greek and Roman European cultures) and where you ?nd numerous places which played a role in ancient science and in early Christianity. Moreover, with the hotel Ceylan Inter-Continental we have found a most excellent me- ing place, directly located at the beach, equipped with wonderful swimming pools and restaurants - an absolutely ?rst-class location. Our NASIwill deal withthemost recent developmentsin high-energyheavy ionphysicsandinthesearchforsuperheavynuclei-tworatherdistinctareasof research. Indeed, we want to bring two very active communities of nuclear and high-energy physics into close contact. The meeting is both a school and has also the character of a conference: A school because there are many advanced students, many of which are themselves already top researchers and who are contributing with their own research in seminars and posters. It is also a c- ference because new results in the exciting and wonderful ?elds of low- and high-energy heavy ion physics will be presented. We are mainly focussing on the topics of superheavy elements and of hot and dense nuclear matter.