Implementing sustainability solutions in Information Technology (IT) or broader - in Information Communications Technology (ICT) - is a challenge but it is essential. The goal of Making IT Sustainable: Techniques and Applications is to show how it has been done, strategies, various solutions, tool sets, and best practices. Various IT areas are investigated - from data center technologies and operations to cloud computing, to green software, to cryptocurrency, to the transformative AI role in making IT sustainable, to quantum and adiabatic computing. The adoption of sustainable IT practices reduces the environmental footprint of IT by advocating for the utilization of renewable energy sources, electronic waste reduction, the design of energy-efficient IT devices, innovative cooling technologies, and circular economy. Sustainable IT is a complex and challenging field. As a result, there are many questions and uncertainties about how to implement sustainable practices across various scenarios. Making IT Sustainable: Techniques and Applications asks several insightful questions: How can environmentally sustainable data centers be built? How do we compare the carbon footprint of data centers versus public cloud, and cloud-focused IT sustainability standards? As growth in data traffic such as video streaming requires additional internet infrastructure, leading to higher emissions, how is this challenge being addressed and how can we improve energy efficiency in IT such as Adiabatic Reversible Computing, use of direct current, and dematerialization are discussed? Readers of Making IT Sustainable: Techniques and Applications will be a very diverse group. First, the readers include IT professionals who are responsible for managing and maintaining IT infrastructure and systems. The book can provide them with knowledge and guidance on how to reduce the environmental impact of their IT operations. Second, business leaders making decisions about the use of IT will find guidance in the book on how to implement sustainable IT practices in their organizations. Academics and researchers interested in the field of sustainable IT will find information and data helping them develop new ideas and innovative approaches to IT sustainability. The goal of IT sustainability is to contribute to making our planet better. Therefore, students who are interested in pursuing careers in IT or sustainability are the most important members of the book audience. The book helps them understand the key role of sustainability in IT and develop skills and knowledge in this field. Overall, everyone who is interested in reducing the environmental impact of IT can benefit from this book on sustainable IT, regardless of their professional background or level of expertise. Making IT Sustainable: Techniques and Applications is written by an IT practitioner actively working in the field of sustainable IT. The author has firsthand knowledge of the challenges and opportunities of implementing sustainable practices in IT operations. Readers will find practical solutions with examples of their implementations.