He worked out a plan to raise India's rate of savings in the post-Second World War period when the country was in need of foreign aid.
Raj joined Delhi University, where he was Professor of Economics and also Vice-Chancellor (from October 1969 to December 1970), spending a total of 18 years there.
After returning to Kerala from Delhi in 1971, Raj set up the Centre for Development Studies at Thiruvananthapuram, an institution that soon acquired an international reputation for applied economics and social science research.
The work that Raj and his colleagues did for the United Nations in the early days of the CDS, and published in 1976, helped shape the contours of what later came to be called the "Kerala model of development" - the co-existence of low per capita income and very high physical quality of life indicators like life expectancy and literacy rate.
Raj once wrote philosophically: "I think that most of the things that welfare economists talk about are those that are obvious to all of us, especially the common people.
In fact, even a pure philosopher and religious thinker like Sree Narayana Guru, who achieved a social transformation in Kerala, spoke about the very same things that welfare economists speak about today: education, health care facilities, even small-scale industries...