This study is aimed at covering all aspects of the evaluation, certification, and reduction of the energy and carbon footprint of the built environment across the globe. The study investigates the topic from the scale of the city and its neighbourhoods, to the building level and finally to the level of single building materials and components. Many protocols, tools, and labels proposed in recent years, both at international and local levels, are compared. The study aim is to classify, describe, and discuss all the different approaches and options. The chapters offer a comprehensive, up-to-date, and critical review of all the different certification methods that have been proposed at different levels in the building sector. Tools and protocols for cities and neighbourhood sustainability assessment for buildings sustainability assessment and certification, and for building materials and components are compared. Finally, the study includes an overview of the legislation and standards in the field and case studies to exemplify the application of the different tools and labels.