The Presidential Commission for the Study of Bioethical Issues seeks public comments on federal and international standards for protecting participants in scientific studies supported by the federal government, including related ethical and social justice issues. In particular, the panel requests comments on such issues as differences across global standards; standards for ancillary care and post-trial access to treatment; trial design; duties to participants; and challenges, if any, faced by U.S.-funded researchers working internationally, or international researchers collaborating on U.S.-funded research. Comments on are due by May 2, 2011.