 Clinical research poses three types of net risks: absolute, relative, and indirect (Rid and Wendler 2011). Absolute net risks arise when the risks of an intervention or procedure are not justified by its potential clinical benefits. Most commentators focus on this possibility with respect to research procedures which pose some risks and offer (essentially) no chance of clinical benefit, such as blood draws to obtain cells for laboratory studies. Research with healthy volunteers is another example which frequently offers no chance for clinical benefit. Clinical research also poses absolute net risks when it offers a chance for clinical benefit which is not sufficient to justify the risks participants face. A kidney biopsy to obtain tissue from presumed healthy volunteers may offer some very low chance of identifying an unrecognized and treatable pathology. This intervention nonetheless poses net risks if the chance for clinical benefit for the participants is not sufficient to justify the risks of their undergoing the biopsy.