Scholars and policymakers continue to struggle over the meaning of the word “vulnerable” in the context of research ethics. One major reason for the stymied discussions regarding vulnerable populations is that there is no clear distinction between accounts of research vulnerabilities that exist for certain populations and discussions of research vulnerabilities that require special regulations in the context of research ethics policies. I suggest an analytic process by which to ascertain whether particular vulnerable populations should be contenders for additional regulatory (...) protections. I apply this process to two vulnerable populations: the cognitively vulnerable and the economically vulnerable. I conclude that a subset of the cognitively vulnerable require extra protections while the economically vulnerable should be protected by implementing existing regulations more appropriately and rigorously. Unless or until the informed consent process is more adequately implemented and the distributive justice requirement of the Belmont Report is emphasized and operationalized, the economically disadvantaged will remain particularly vulnerable to the harm of exploitation in research. (shrink)