This paper analyses the effects of research assessment on the overall research practices of academics. Case study research was conducted in departments from two contrasting disciplines -- the natural sciences and the humanities -- in one research intensive Danish university. The case studies examined academics' and administrators' experiences of a national bibliometric indicator (BFI) used for research assessment. PhD students and early career researchers reported that the greatest effects of research assessment were on their publishing practices. Prompted by further questions, many interviewees reflected on the relationship between research assessment and changes in their overall research practice about which they were previously unaware. We drew on Bourdieu's theory of practice to theorise why there was so little reflexivity, especially among senior researchers, about the relationship between actions to comply with research assessment and changes in research practice itself. We conclude by highlighting some potential implications, especially for mentorship of early career academics.