Activism and scientific research pull on each other with delicious tension. Activism requires action in the face of uncertainty; research requires skepticism. For me, each informs the other. It is absurd to believe that our research is not influenced by our beliefs, and it would be irresponsible in the extreme to let our actions fly in the face of good research. Climate change resulting from human activity is a fine example; as a meteorologist, it is impossible to say that this hot summer or that hurricane results directly from climate change, or even that a string of hot summers are unequivocal evidence. However, both the evidence and the severity of the effects have long since passed the threshold were action is essential. Stratospheric ozone depletion is another excellent example of such a situation; a morality tale that we can now follow from start to evidently successful global action. We can study this example as a social example and as a scientific one. In Global Atmospheric Chemistry I raise the scientific questions; How do we pose and answer the key scientific questions in these complex systems? What can we learn from the stratosphere that applies to climate? To urban air pollution? To other pressing environmental problems? I am in this area because I believe these are crucial problems to solve in a sustainable society, and because the science is just plain delicious. My goal is to share that dual motivation with students at all levels. See the website for The Center for Atmospheric Particle Studies to learn more about Neil's work.