Public sector organisations across the world are increasingly using advanced management concepts. One such concept, internal control, is a set of management arrangements designed to achieve an organisation’s objectives on time, to appropriate performance standards, within budget, efficiently, effectively and in compliance with the law. These Guidelines explain in detail how to develop internal control in public sector organisations and how to assess the quality of existing systems. They are intended to guide ministries of finance and public sector managers in EU candidate countries and potential candidates, but could also be used by other administrations interested in assessing or improving their management and control systems.