In the long run, mitigating climate change and adapting to the phenomenon will prove multi-billion dollar issues. Rich nations have pledged to make an annual $ 100 billion available to developing countries from 2020 on for these two purposes. In the short run, however, the scenario is confusing. So far, there has been far too little tangible action. The institutional architechture, moreover, remains incomplete and inconclusive. To improve matters, humanity needs a comprehensive climate agreement. Such an agreement must define binding targets for all parties to reduce greenhouse gas emissions and thus create a reasonable context for an effective international cap-and-trade system.