Geoengineering (GE) raises grave ethical concerns. Even some GE research is ethically problematic. The principles and institutions created to govern GE research could also provide a foundation for the regulation of GE deployment, if that ever becomes necessary. The ethical principles for regulating GE deployment, however, will differ from those for regulating research, just as the ethical principles for medical practice differ from those for medical research. Similarly, the ethics of GE research differs from the ethics of deploying GE or of implementing any other risk-laden public policy that aims to produce benefits other than knowledge. The Principle of Respect requires that decisions about such GE research be made by legitimate international bodies. The need for regulating GE research is coming faster than the need to regulate GE deployment. Fortunately, the existing framework for regulating other research provides a model for regulating GE research.