Ideas on how to engineer Earth's climate, or to modify the environment on large scales to counter human impacts, do not enjoy broad support from scientists. Refereed publications that deal with such ideas are not numerous nor are they cited widely. Paul Crutzen (2006) analyzes the idea of intentionally injecting sulfur into the stratosphere, to enhance the albedo of Earth, so as to slow the warming of the planet due to greenhouse gases. He notes that such an intervention might become necessary unless the world becomes more successful in limiting greenhouse gas emissions and/or if global warming should proceed faster than currently anticipated partly due to cleaning the lower atmosphere of sulfur pollution (Andreae et al., 2005;Charlson et al., 1991).I am aware that various individuals have opposed the publication of Crutzen's paper, even after peer review and revisions, for various and sincere reasons that are not wholly scientific. Here, I write in support of his call for research on geoengineering and propose a framework for future progress in which supporting and opposing viewpoints can be heard and incorporated. I also propose that research on geoengineering be considered separately from actual implementation, and I suggest a path in that direction.