Growing emphasis has been placed on universities to contribute to the innovation process and as a result academic research and development expenditures have increased in recent years. Nevertheless, little is known about the specific ways in which universities have expanded their research capacity. This paper examines how universities in the United States (US) have expanded research capacity as research funding has increased. Specifically, it identifies what type of research infrastructure, including various categories of human capital and research equipment, are most closely associated with increased academic research funding. Using data from 375 US universities spanning the period 1990-2005, through multiple regression analysis this study finds that "traditional" and new "market" based elements of research capacity are associated with increased research funding. The implications of this study extend beyond the US since many countries are both investing in expanding research capacity and transforming the way research is organised within universities.