The 21st century is a new century full of challenges and opportunities. In such a diversified and changing environment, the management of enterprises experiences substantial revolutions. As a managerial control mechanism that ensures effective accountability, internal audit has to change with it in order to become an essential part of the value chain and to provide "value-added" service to enterprises. Risk-oriented internal audit is the latest development of internal audit. Internationally speaking, the research on its theories and practical issues is still on preliminary stage. In 2003, the China Institute of Internal Audit issued the first internal audit standards, which is the first step to promote the profession of internal audit in China. Comparing to international researches, the research on internal audit theories and practical issues in China is very weak, which also indicates an extensive space in this area. This paper researches the frontier of internal audit ?risk-oriented internal auditing, which is supposed to have theoretical as well as realistic significance. This paper is organized as follows:InstructionThe instruction part discusses the motivations, rational, research methods, structure and major issues of the paper.Chapter One Historical Evolution of Internal Audit Theories and PracticesThis chapter reviews the historical evolution of internal audit, from germination stage to financial-oriented stage, operational-oriented stage, management-oriented stage and risk-oriented stage. Managerial theories and practices affects the evolution of internal audit substantially and the process reflects the changes in the accountability relationship on which internal audit relies. It also describes the practices and key viewpoints of theory of every stage of internal audit.Chapter Two Basic Theories of Risk-oriented Internal AuditThis chapter dissertates the background and basic theories of risk-orientedinternal audit. The development of risk-oriented internal audit is following the historical evolution rule concluded in Chapter One. This chapter then constructs a systemic risk-oriented internal audit theory structure.Chapter Three Risk-oriented Internal Audit and Corporate Governance This chapter examines the relationship between internal audit and corporate governance and describes the evolution of the traditional internal audit reporting relationships to corporate governance. Then it analyzes the more closely interactive relationship between risk-oriented internal audit and corporate governance. Except providing double-direction motile reports to audit committee and executive managements, risk-oriented internal audit takes corporate governance as its object and promotes it directly.Chapter Four Risk-orient Internal Audit and Internal Control This chapter examines the relationship between internal audit and internal control. It describes the role of tradition internal audit in internal control on the basic of the analysis of the relationship between managerial control and internal control. Then it analyzes the relationship between risk-oriented internal audit and the modern internal control which is developed to enterprise risk management framework. It also introduces some special techniques of risk-oriented internal audit.Chapter Five The Role of Risk-oriented Internal Audit in the Integrated SystemThis chapter is the conclusion of the previous parts. It analyzes the formation of the integrated system of corporate governance and internal control on the basic of systematic theory and describes the feedback function of risk-oriented internal audit in the integrated system. This part thus further suggests that risk-oriented internal audit promote the combination of corporate governance and internal control, which then promote the unification of internal and external accountability of enterprises.Chapter Six Indications of Risk-oriented Internal Audit to the Future of Internal Audit in ChinaThis chapter firstly describes the history of internal audit in China, then compares the