This book deals with consensual mechanisms in criminal proceedings analyzed comparatively. In the first place, it addresses the common systemic foundations of consensual mechanisms and the observation of most up-to-date supranational trends in their development. In the second place, it presents phenomenon of negotiated justice outside the common law systems through examples of Poland, Germany and Brazil. The combination of these two approaches provides a good basis for observation on the general advantages and disadvantages of negotiated justice. It also helps for balancing the optimal extensiveness of its use in the contemporary criminal proceedings.