First Republic of South VietNam, Khương became the Director of Industrial Development Center and Industrial Development Bank of VietNam. He held this position from 1964 until the Fall of SàiGòn in 1975. Concurrently, under the government of Prime Minister – Air Marshal Nguyễn Cao Kỳ, Khương was the Minister of Economy (Commerce, then Industry) from 1966 to 1968. In 1975, South Vietnam lost the war, many Vietnamese refugees immigrate to the United States. Khương settled in San Francisco, California and joined Bechtel Corporation in San Francisco as an Assistant Project Manager. He held this position until 1987. In 1987, Khương joined MDA Engineering Inc. of Hayward, California as a Principal and Vice President until his retirement from business and professional life in 1996. When Prime Minister Nguyễn Cao Kỳ formed a new government Khương held the position of Minister of Commerce concurrently with the position of President and CEO of Industrial Development Bank. In 1969, Nguyễn Văn Thiệu established the 2nd Republic of South VietNam, Khương continued holding the position of President and CEO of Industrial Development Bank of South VietNam until the fall of Saigon on 30 April 1975. Khuong did represent the government of South Vietnam to speak at many international banking and economic summits: "The potential for postwar industrial development in Vietnam : American-Vietnamese Seminar on Trade, Investment and Development, sic. ; Center for International Business, Honolulu, 29 May–June 1, 1973" , "A study of oxy-gasoline flame as applied to oxygen cutting" . In 1974, prior to end of the Vietnam War, Khuong discussed at an international forum about Vietnam's future in education. WikiLeaks recently published a "Declassified CIA Document" about this topic . The conference was well received by thousand attendees. During his official roles with South VietNam government, Khương did many lectures, participated as board members of various organizations as follows: Lecturer, Phú Thọ Technical Institute, Saigon, VietNam between 1966 and 1970. Lecturer, Cao Đẳng Quốc Phỏng (National Defense College) between 1966 and 1972 Board member of Vietnam Power Company between 1969 and 1975 Board Member & Vice President of Sicovina Textile Company between 1965 and 1975 President of American University Alumni Association between 1968 and 1971 Board Member & President of Vietnam-American Association between 1972 and 1975 Founder and President of Vietnam Management Association between 1966 and 1975 Board Member & President of Asian Productivity Organization, Japan between 1965 and 1975 Head of Vietnam