Today, we interviewed Bob Watson at the World Bank Group. Coincidentally, this is his last day on the job before he moves back to England to assume three different positions in the academic and policy worlds. It is also the last of 12 people Dan and I have interviewed all over the country (10 cities, 7 states) for this film about the struggle to save the ozone layer. In Watson, we may have saved the best for last. Having spent the past 15 years or so at the World Bank Group, Watson may be the world’s foremost expert on the interface between sustainable development and environmental issues. Mack McFarland told us that Watson basically invented the notion of the international scientific assessment, which united the voices of scientists everywhere so they could have more credibility with politicians. This process, refined during the 1980s, was critical for reaching scientific consensus and political agreement on how to deal with ozone-depleting substance. Today, the process is even more mature—and with regard to the climate challenge, is the the Intergovernmental Panel on Climate Change.