In recent years, the Vietnamese government has put significant effort into the internationalization of research in the higher education system via the use of international publications (i.e., publications indexed by citation databases such as ISI Web of Science and Scopus) in evaluating their academic staff and doctoral students. Academic staff in Vietnam, who traditionally have low numbers of international publications, have thus been pushed to improve their competencies in order to meet the new requirements for research productivity. However, we have little understanding of the factors influencing international publication as perceived by Vietnamese academic staff. This study aims to fill the gap by using the Delphi method. Academic staff with at least one international publication were invited, via purposeful sampling, to participate in a two-round Delphi survey. The survey revealed 14 key factors, which were further classified into three dimensions: "policy-related factors," "capability-related factors," and "networking-related factors". These factors were the key determinants in the success of international publishing, according to the study participants. The findings provide implications for policymakers and university leaders for enhancing the research capacities of Vietnamese universities, forming a basis for the sustainable development of the higher education sector in Vietnam.