Steve Macmillan, seconded from Origin Energy (Australia) is the main author of the first chapter. The author wants to thank for their contributions the following staff from the IEA: Dennis Volk, Christina Hood, Simon Mueller, Alexander Antonyuk, Grayson Heffner, Justine Garett, Andre Aasrud, Cedric Philibert and Johannes Truby. Only a few years ago there was confidence that liberalised electricity markets in IEA member countries could also deliver sufficient and timely generation investments needed to ensure security of supply.