In this article, we assert that developing countries are much better prepared to undertake negotiations at the Conference of the Parties in Paris (CoP21) as compared to CoP15 in Copenhagen. An important element of this is the accumulation of knowledge with respect to the implications of climate change and the ongoing internalization thereof by key institutions in developing countries. The articles in this special issue set forth a set of technical contributions to this improved understanding. We also summarize five major lessons related to uncertainty, extreme events, timing of impacts, the inseparability of the development and climate agendas, and the rate of assimilation of climate and development information in key institutions. They are drawn from the Development Under Climate Change (DUCC) project carried out by UNU-WIDER of which the countries of the Greater Zambeze Valley formed a part. Finally, we outline three areas for future research.