In 1954, Goh was able to return to LSE for doctoral studies with the help of a University of London scholarship. He completed his PhD in Economics in 1956, and returned to the Department of Social Welfare, where he served as assistant director and then director. In 1958 he was made director of the Social and Economic Research Division in the Chief Minister's Office. He resigned from the civil service in August that year to work full-time for the People's Action Party (PAP).