This paper aims to unveil the reasons behind the changes in HK's Mathematics Curriculum in the last two decades. It attempts to find out what actually initiated new Mathematics Syllabuses in HK. Besides literature search on relevant documents, archives and government printings, personal interviews of renowned mathematics educators were also conducted. Seven major motive forces were identified. Their social, economical, political settings and their implications on mathematics education were also discussed.[Copyright © 2000 The Hong Kong Institute of Education.]