School curriculum development is an important task for school instructional supervisors. In September 1998, The Ministry of Education of R.O.C. promulgated the general principles of the nine-year integrated curricula (1st-9th grades) which will begin in the year 2001. The new curricula creates substancial changes and will give schools more leverage to decide what needs to be taught within their own schools.In order to successfully implement the new curricula, it is very important to emphasize the function of instructional supervision within schools. A principal is responsible for enhancing teacher involvement levels in curriculum development and to lead school teachers to develop school curriculum cooperatively. A principal should also organize a school curriculum development committee and a task force within his own school to analyze written curriculum, textbooks and standardized tests. Every school needs to revise its own curriculum depending upon the results of students' achievements, the reaction of school teachers and communities, and suggestions of curriculum experts.