This group interview with Michael Edgeworth McIntyre, Joseph Farman, J. D. Shanklin, Tony Cox, Ian W. M. Smith, Neil R. P. Harris, H. Graf, and Peter Braesicke discusses the way scientists of the 1970s and 80s learned about ozone depletion. Topics discussed include: Intergovernmental Panel on Climate Change (IPCC); Antarctic ozone hole; chlorofluorocarbons; Montreal Protocol; climate change policy; carbon dioxide; DuPont company; Mack McFarland; F. S. Rowland; Mario Molina; polar stratospheric clouds (PSCs); Pat McCormick; Climate Impact Assessment Program (CIAP).