Professor Gopal Sreenivasan delivers a New St Cross Special Ethics Seminar on the topic of Informed Consent. This talk develops a novel argument to show that prospective research subjects can validly consent to participate in a study without understanding (most of) the content of the required disclosure. Its point of departure is the right subjects standardly have to waive (most of) the investigator’s duty to disclose. Things get worse for autonomy based defences of informed consent because this right to waive is very well grounded in an individual’s autonomy.