This document discusses research at IRRI related to trade-offs in climate change. It summarizes several projects measuring greenhouse gas emissions from rice production. Alternate wetting and drying reduces CH4 emissions from rice but can increase N2O emissions. It also discusses developing a new methodology for the Clean Development Mechanism that establishes default values for reducing CH4 emissions through intermittent flooding in rice production. Accurate sampling is important for estimating seasonal GHG impacts. The research aims to balance scientific accuracy with potential impact.