This book is the latest work on the reform of supervisory system by Qin Qianhong. The author demonstrates China's supervisory system at both the theoretical and practical levels, discusses the historical development of supervisory system reform in depth and offers the prospect of supervisory system from his unique perspective. Theoretically, focusing on the context of China, the book studies systematically the origin, transformation and evolution of the concept of supervision and concludes the theoretical basis, object of research and basic scope of supervisory law research, in expectation of building a theoretical system. Practically, from the perspective of China's reality, the book focuses on the studies of the crucial issues in supervisory system reform, such as the cooperation between supervisory power and prosecutorial power, and the status of supervisory institutions, aiming to provide suggestions for the supervisory system reform.