Concerns about privacy may deter people from participating in genetic research. Recruitment and retention of biobank participants requires understanding the nature and magnitude of these concerns. Potential participants in a proposed biobank were asked about their willingness to participate, their privacy concerns, informed consent, and data sharing. A representative survey of 4659 U.S. adults was conducted. Ninety percent of respondents would be concerned about privacy, 56% would be concerned about researchers having their information, and 37% would worry that study data could be used against them. However, 60% would participate in the biobank if asked. Nearly half (48%) would prefer to provide consent once for all research approved by an oversight panel, whereas 42% would prefer to provide consent for each project separately. Although 92% would allow academic researchers to use study data, 80% and 75%, respectively, would grant access to government and industry researchers. Concern about privacy was related to lower willingness to participate only when respondents were told that they would receive $50 for participation and would not receive individual research results back. Among respondents who were told that they would receive $200 or individual research results, privacy concerns were not related to willingness. Survey respondents valued both privacy and participation in biomedical research. Despite pervasive privacy concerns, 60% would participate in a biobank. Assuring research participants that their privacy will be protected to the best of researchers' abilities may increase participants' acceptance of consent for broad research uses of biobank data by a wide range of researchers.