The field of bioethics has had a long preoccupation with payment for research participation. The end result of these debates has largely been consensus that there is nothing ethically wrong with paying people to participate in research and yet it does not feel quite right either. This discomfort is particularly striking when it comes to paying healthy individuals to enroll in Phase I clinical trials that test the safety and tolerability of investigational drugs because these studies can pay substantial sums of money (at least compared to other research) and because there are so-called professional guinea pigs who treat these clinical trials as a job. The two articles published in this issue of AJOB shed light on these topics, with Millum and Garnett (2019) focusing on the problem of how compensation can raise important ethical concerns that are separate from the consent process itself and Malmqvist (2019) interrogating the nature of work to query whether healthy volunteers should be considered workers. These articles offer much to debates about payment for research participation, but they also both miss an important ethical concern that emerges when financial compensation is offered in contexts of profound social and economic inequality.