Responsible conduct in science is more than simply a matter of following everyday ethical imperatives—not misreporting what actually happened in the lab, dealing honestly with colleagues, and so forth. Scientific responsibility arises because scientists play a special role, and that role brings obligations. In this article I maintain that scientists have an obligation to reflect on the ends of scientific research; that scientists should work for the public good, directing their efforts toward an ideal of well-ordered science; and that the ideal of well-ordered science should be understood in a global and democratic fashion.