Identifying factors that affect research productivity is critical to both the scientific community and policy-makers. This topic is especially useful for developing countries like Vietnam where such studies are scarce with limited original data. This paper, through a manual data collection process that yields the profiles of 406 Vietnamese social scientists with publications in Scopus-indexed journals in 2008-2017, uses the ordinary least squares method to analyse the effects of two factors on research productivity. It adds to the literature by showing the extent to which (i) work environment ('universities' and 'research institutions'); (ii) collaboration affect the adjusted research productivity of social scientists. Contrary to the usual belief, university-affiliated authors in Vietnam turned out to have higher research productivity than institution-affiliated peers. International collaboration could boost research output, although this effect is insignificant among the high-performing authors. The paper also suggests some policy implications for Vietnam facing challenges in science management.