This is the first interdisciplinary work to address the fundamental scientific problems in ultra-high dilution and homoeopathy. A brief introduction into the scientific history of homoeopathy familiarises the reader with the concept of homoeopathy as well as the scientific problems in characterising the efficacy of homoeopathy and phenomena observed in ultra-high dilutions. A large part of the book covers the fundamental theoretical medicine and physics of homoeopathy. Based on the solid ground of modern physics, the reader will learn about the energetics, entropic and electrodynamics of ultra-high dilutions from the perspective of leading physicists and biologists who bring the findings of basic science into the field of ultra-high dilutions and homoeopathy. The theoretical medicine and physics set the basis for a critical evaluation of the fundamental experiments presented, which employ botanical and zoological bio-assays and immunology as well as reaction cybernetics. The book also includes a critical review of clinical trials as well as a presentation of the research strategy into homoeopathy as recommended by the European Commission for Homoeopathy. This book is a rich source of references and concepts and should command wide interdisciplinary attention. Graduate students in medical and health sciences will find the book interesting and it will be appreciated by researchers in physical and medical sciences as well as practitioners in homoeopathy.