5G, the emerging technology in mobile communication, is expected to deliver an important and decisive impact on several of the UN’s Sustainable Development Goals where universal accessibility to ICTs remains a serious concern.However, cyber security has emerged as a serious challenge, not least because of the increased accessibility and broader usage with associated vulnerability.Developing countries have additional challenges associated with both the expected faster build-up of accessibility and lack of qualified competencies within cyber security.Discussion of these challenges is the overall theme and motivation for this book. Technical topics discussed in the book include:5G in rural networksCritical infrastructuresOpen RANProtection of privacyCybersecurity and machine learningCybersecurity and disaster monitoring