1 Chiral Symmetry and the BAG Model: A New Starting Point for Nuclear Physics. - 1. Introduction. - 2. The Basic Bag Model. - 3. Hadronic Properties in the MIT Bag Model. - 4. Chiral Symmetry. - 5. Bag Models with Chiral Symmetry. - 6. Applications of the Cloudy Bag Model. - 7. Towards a New View of Nuclear Physics. - 8. Conclusion. - Acknowledgements. - Appendix I. - References. - 2 The Interacting Boson Model. - 1. Introduction. - 2. The Interacting Boson Model-1. - 3. Geometric Properties of the Interacting Boson Model-1. - 4. The Interacting Boson Model-2. - 5. Microscopic Description of Interacting Bosons. - 6. Conclusions. - Acknowledgements. - References. - 3 High-Energy Nuclear Collisions. - 1. Introduction. - 2. Theoretical Tools. - 3. Elements of the Reaction Mechanism. - 4. Toward the Physics of Dense Nuclear Matter. - 5. Summary and Outlook. - Acknowledgments. - Appendix: Definition of Common Variables. - References. Language: English