The paper investigates the potential impact of entrepreneurial motivation, entrepreneurial intention and academic researchers' perceptions of departmental and university support on academic entrepreneurial engagement in the context of weak or missing institutional support. A conceptual model linking motivation, intention and perceptions to entrepreneurial engagement is developed and tested on primary data collected from academic researchers in Nigeria. We find that while entrepreneurial motivation strongly influences the entrepreneurial intentions of researchers, the link between intention and engagement is weaker. Perceptions of departmental entrepreneurial orientation positively mediate a significant proportion of the latter link. In contrast, perceptions about the university's supportive framework and facilities play a relatively weaker role. Subsequently, the implications of these findings on policies and incentives for entrepreneurial academics and universities in weak institutional settings are explored.