The search for a quantum gravity theory a theory expected to combine the principles of general
relativity and quantum theory has led to some of the most deepest and most difficult
conceptual and mathematical questions of modern physics. The present book addressing these
issues in the framework of recent versions of canonical quantization is the first to present
coherently the background for their understanding. Starting with an analysis of the structure
of constrained systems and the problems of their quantization it discusses the canonical
formulation of classical relativity from different perspectives and leads to recent
applications of canonical methods to create a quantum theory of gravity. The book aims to make
accessible the most fundamental problems and to stimulate work in this field.
