Since the late 1980s, policy makers and regulators in a number of countries have liberalized, restructured or ''deregulated'' their electric power sector, typically by introducing competition at the generation and retail level. These experiments have resulted in vastly different outcomes - some highly encouraging, others utterly disastrous. However, many countries continue along the same path for a variety of reasons.This book examines the most important competitive electricity markets around the world and provides definitive answers as to why some markets have performed admirably, while others have utterly failed, often with dire financial and cost consequences.The lessons contained within are direct relevance to regulators, policy makers, the investment community, industry, academics and graduate students of electricity markets worldwide.