This chapter draws on self-determination theory to explain the mix of pecuniary and non-pecuniary motivational drivers underlying academic scientists´ commercial pursuits. It examines the diversity of their personal motivations for knowledge commercialization and how this is influenced by their values and beliefs about the science-business relationship. It argues that scientists can be extrinsically or intrinsically motivated to different f in their pursuit of knowledge commercialization, depending how far they have internalized the values associated with it. Beyond reputational and financial rewards, intrinsic motivations (e.g., pro-social norms and hedonic motivation) are also powerful drivers of commercial engagement. The conventional assumption that scientists are motivated by reputational rewards and the intrinsic satisfaction of puzzle-solving in academic research while commercial engagement is driven primarily by the pursuit of the financial rewards builds on a false dichotomy and polarized view of human motivation.