2009年，香港開始新高中課程改革，一個新的必修科目通識教育科是其中一個重要的改革舉措。本文通過一項質性的研究，從人力成本的角度分析通識教育科從2006年開始推出到2009年正式實施時教師的準備與實施情況。研究發現通識教育的變革是一個包括大量任務成本、社會成本和心理成本的變革，教師實施起來十分困難，需要大量時間與努力；同時變革也改變了原來的教師結構，產生兼教的心態；教師們缺乏自信，產生專業身份的危機。不論通識教育改革能否實現其宏大的教育目標，這一變革需要人力成本的大量投入，對教師和學校來說，都是一個很大的挑戰，也很可能影響改革的可持續性。

Liberal Studies, a new compulsory subject, is probably the most important initiative of the senior secondary curriculum reform implemented in Hong Kong in 2009. This paper reports the findings of a qualitative study which reveals the human costs involved in the preparation and implementation of the subject by schools and teachers from 2006 to 2009. It is found that the implementation of this compulsory subject was very costly, in particular the task cost, social cost and psychological cost. Teachers found putting this new subject into practice is a very difficult task as it demanded much effort and time. The new subject also led to changes in the structure of staffing in schools. Many teachers has to teach a new subject, hence affected their self-confidence and created subject identity crisis. At present stage, it is not sure whether this curriculum change will achieve the ambitious goals. But it definitely demands huge cost. To teachers and schools, this is a huge challenge and the sustainability of the change is questionable.