Nine theses on the morality of climate engineering: Should we engineer the climate? What speaks in favour of doing it and what against? Answers to these questions must be based in empirical science. But they must also engage with moral questions - those about duties, norms and values - if they want to do more than simply name what is feasible. In this contribution we defend 9 theses on the ethics of climate engineering (CE). We discuss which ethical aspects are of particular importance, what opportunities and risk matter most from a moral point of view, and how the debate on CE reflects upon us.