Economist Lawrence Summers has presented 4 steps for climate control. He (or his newspaper sub-editor) calls them practical, but given the political will and multi-national collaboration required, they do not appear all that practical.
“First, the US must engage in an energy efficiency programme that takes effect without delay and has meaningful bite. As long [...]

Several leading academic economists, writing in the Review of Environmental Economics and Policy Journal, have praised the European Emissions Trading Scheme, according to the FT.
“The economists, including Denny Ellerman of MIT, Barbara Buchner of the Fondazione Eni Enrico Mattei, Frank Convery, Joseph Kruger and William Pizer, said the European Union scheme should form the [...]