This unique compendium gives an overview of the current research activities and developments within the areas of quantum hardware, quantum computing, quantum software, quantum communication and quantum sensing in Denmark. Renowned contributing authors are part of the Danish research community and work in research institutions or companies dealing with and related to quantum technologies.The useful reference text allows readers to identify the research groups within Denmark working on specific topics as well as learning about topics which might be unfamiliar to them. The intention of each chapter is to give a good introduction to the scientific theory and the current state of the art.