As the quality of higher education institutes is becoming more emphasized nowadays, accountability and institutional enhancement should be inextricably linked. This paper describes how accountability is formed, the content of accountability, and the accountability subjects, such as government, society, markets, students, institution, self and colleague. In addition, a school should establish an effective internal accountability system to support itself under the external pressure. This paper addresses some accountability models such as, ADRE, TQM, ISO9001, MBNQA, assessment, and balanced scorecard. It also introduces the external accountability systems, and the trend of performance budgeting, funding and reporting. Finally, it summarizes that quality audit is one of the best mechanisms that can be applied internally and externally.