Although informed consent is important in clinical research, questions persist regarding when it is necessary, what it requires, and how it should be obtained. The standard view in research ethics is that the function of informed consent is to respect individual autonomy. However, consent processes are multidimensional and serve other ethical functions as well. These functions deserve particular attention when barriers to consent exist. We argue that consent serves seven ethically important and conceptually distinct functions. The first four functions pertain (...) principally to individual participants: (1) providing transparency; (2) allowing control and authorization; (3) promoting concordance with participants' values; and (4) protecting and promoting welfare interests. Three other functions are systemic or policy focused: (5) promoting trust; (6) satisfying regulatory requirements; and (7) promoting integrity in research. Reframing consent around these functions can guide approaches to consent that are context sensitive and that maximize achievable goals. (shrink)