This open access book invites readers to explore the emerging opportunities and strategic significance of quantum technologies in the context of cybersecurity.It collects the latest trends and insights into the evolution of quantum computing and quantum communication, offering valuable guidance.To this end, it brings together comprehensive trends, research, and insights from more than 40 leading experts from around the globe to provide a deep understanding of the opportunities, challenges, and implications of quantum technologies for cyber defence. Divided in three parts, the book examines core advancements in various types of quantum technologies and also addresses the key obstacles that limit progress.It explores the potential disruptions to current cryptographic standards alongside potential solutions, as well as global quantum strategies and tools designed to monitor trends in quantum technologies. This is the third book in a series published by the Technology Monitoring (TM) team of the Cyber-Defence Campus.It serves as a resource for researchers, cybersecurity specialists, policymakers, and industry leaders navigating the rapidly evolving quantum landscape.It aims to foster informed decision-making and encourage collaboration across sectors.