IETA President, Henry Derwent, discusses regional emissions trading systems with Climate-Change.tv. He explains how time is key to bringing the systems together and how market solutions are absolutely necessary to combating climate change. He stresses the importance of including the potential for new mechanisms within any agreement. Also see Henry Derwent, speaking from Poznan in 2008. And Teresa Ribera Rodriguez, the Spanish Secretary of State for Climate Change, also from Poznan.