This book presents selected papers from the 2nd International Conference on Emerging Trends in Cyber Security (ICETCS-2025) held in October 2025, at Wolverhampton, United Kingdom. This book covers a broad spectrum of topics, including the latest innovations in cyber defense mechanisms, the integration of AI in cybersecurity, and the challenges of protecting increasingly complex networks and systems. Key areas of discussion include blockchain for enhanced security measures, machine learning for threat detection, advanced cryptographic techniques, and strategies for securing cloud environments and IoT systems. This book delves into the potential and challenges of new cybersecurity paradigms, exploring advanced frameworks and methodologies that aim to bolster defenses against sophisticated cyber threats. The content is relevant to leading researchers, practitioners, and thought leaders from academia, industry, and government who are interested in the best practices and policy-making, all aimed at enhancing global cybersecurity resilience.