Research involving children or other incompetent subjects who are deemed unable to provide informed consent is complex, particularly in the case of research that does not directly benefit the research subjects themselves. The Helsinki Declaration, the World Medical Association's landmark document for research ethics, therefore states that incompetent research subjects must not be included in such research unless it entails only minimal risk and minimal burden. In this paper, we argue that now that research in these groups is expected to (...) expand, this undifferentiated minimal risk and burden requirement does not suffice any more. In the upcoming revision of the Declaration, the paragraph at stake should be refined in such a way that it is not unnecessarily restrictive or more permissive than can be ethically justified. Our first recommendation is to stimulate research ethics committees to identify more accurately those risks and burdens that the research subjects must undergo solely for research purposes by distinguishing between two types of study procedures instead of between two types of studies. Our second recommendation is to allow for exceptions to the minimal risk and burden requirement in cases of exceptionally valuable studies that involve subjects who can give their assent to participate in the study and that involve at most a minor increase over minimal risk and/or burden. (shrink)