The security policy situation in Europe has changed in recent years. In many member states, awareness of the importance of the EU's Common Security and Defence Policy (CSDP) has grown. This applies in particular to those states "on the periphery" that have a special constitutional status with regard to their defence policy and are particularly exposed to external security threats or, on the contrary, are geographically particularly distant from them. The Walter Hallstein Symposium 2023 focussed on these recent CSDP developments. This anthology brings together the conference papers that trace the developments up to the end of 2023.With contributions byProf. Francisco Pereira Couthino; PhD Prof. Dunja Duic, PhD, LL.M. (Ghent) Prof. Dr. Frank Hoffmeister Prof. Dr. Dr. Rainer Hofmann Prof. Dr. Stefan Kadelbach, LL.M. Prof. Dr. Dr. h.c. Herbert Küpper Dr. Carolyn Moser, MA. Prof. Dr. Andreas Müller, LL.M. (Yale) Prof. Manolis Perakis