There has been much interest in studying events with tagged forward protons at the existing and forthcoming hadronic colliders, the Tevatron and the LHC. These studies not only allow one to monitor the luminosity of the colliding protons with high accuracy but also provide new ways of investigating the subtle issues of QCD dynamics and searches for the manifestations of new physics. This book reviews the state-of-the-art of forward physics measurements and the theoretical development. It catalyzes many new approaches within the framework of the extensive physics programme of the LHC. This in...