This book aims to provide an overview of crucial aspects related to the interconnection between the political economy of energy security and national security, which is of great importance globally due to high volatility and complexity. In this book, contemporary energy issues in relation to the energy security are examined, along with main vulnerabilities and challenges that have appeared lately with an impact beyond country borders and with a particular focus on the Eastern Mediterranean region. Energy security is studied on both International and European level and finally the Eastern Mediterranean region with special reference to the countries of the State of Israel and the Republic of Cyprus. The rapidly changing geopolitical environment makes energy security one of the critical areas of immediate interest that need a holistic approach. The importance of energy security in the Eastern Mediterranean region is constantly growing and requires the proper vision to enhance security in the region. Energy is now linked to the issues of sustainable development and tackling climate change, which is also taken into account. Finally, this book is expected to contribute to the existing literature and provide an in-depth study that gives a fresh approach to the academic and political community.