Authoritative and comprehensive guide illustrating best practices for designing and building resilient and sustainable smart cities Digital Twins evaluates smart city case studies and insights from the 100 IEEE IoT Global Cities Alliance (GCA) and describes best practices and standards for designing secure architecture using IoT, IoP, and AI. Showcasing success stories while also examining common issues from smart city projects around the world, this guide unpacks lessons learned and identifies where to further integrate standards into city frameworks and processes. Featuring chapters on water, food, energy, mobility, health, waste, education, economies, and work, the environment, social wellbeing, ethics, security, and privacy, the text demonstrates the impact of smart cities on our daily lives. The authors describe the sustainable needs for our next generation and identify the challenges and changes needed to implement smart cities. Readers will learn about Smart City Digital Twins (SCDT), and international Urban Twins (UT), based on architecture, building information modeling (BIM), and big data, which support municipalities to digitally simulate 3D models and create scenarios to test strategies and plans for urban planning, mobility, and disaster management. Other topics covered in Digital Twins include: Models and open data pertaining to smart city governance, and standard requirements for architectures to integrate IoT solutions in Smart Cities Factors and best practices for different global regions when implementing IoT Solutions and future trends and challenges as areas of opportunity Key discussion points to keep in mind on the digital transformations of cities, such as problem solving in relation to city similarities and differences Snapshots of five cities, covering their approach to becoming a sustainable smart city and undertaking their respective digital transformations Representing the latest developments and future trends of IoT and smart connectivity, Digital Twins is an ideal resource for municipalities and practitioners within the field of smart cities as well as those working more broadly on sustainability and technology who wish to learn about a wealth of topics intersecting with smart cities.