AN EXAMINATION ON THE INTERNAL QUALITY ASSURANCE SYSTEMS OF OPEN AND DISTANCE LEARNING INSTITUTIONS The purpose of the study is to determine principles that will guide open and distance learning institutions in the world and in Turkey to establish and improve their internal quality assurance systems. In this regard, internal quality assurance processes of three open and distance learning institutions which possess successful open and distance learning practices were examined. The study was designed as holistic multiple case study. In order to reflect the differences in the quality assurance practices, purposeful sampling method was used and three open universities possessing different characteristics from three different regions, which were America (Canada), Europe (Spain) and Asia-Pacific (Japan), were examined. Data were gathered through site visits, semi-structured and unstructured interviews, and documents. As a consequence, some guiding principles were determined and recommendations were made for the establishment, implementation and development of internal quality assurance systems in open and distance learning institutions both in Turkey and the world