Assistant Director-General, World Health Organization since 1988. World Health Organization Representative, Regional Office for the Western Pacific, Philippines, 1986-1987. Regional Advisor, 1979-1986, Consultant, 1978-1979, Maternal & Child Health/Family Planning, World Health Organization, Philippines.
Director & Professor, Department of Pediatrics, Deputy Director, Rch Unit/ Haematology, Shanghai Second Medical College, China, 1973-1978. Deputy Director, Department of Pediatrics, Rui-Jing Hospital, Shanghai Second Medical College, 1970-1972. Team Leader, Mobile Medical Team, Song-Jiang County, Shanghai, 1968-1969.
Chief Physician, Consultant, 1962-1966, Resident and Chief Resident, 5662, Kuang-Ci Hospital, Shanghai.