This book was planned and written in view of the controversy associated with the usage of methyl tertiary-butyl ether (MTBE) in reformulated gasoline, generally in the United States and particularly in the state of California, which has sparked global discussions and arguments on the benefits and hazards associated with MTBE usage. The studies and arguments reflect both positive and negative aspects of MTBE. An effort has been made in this book to present studies, views, and reviews from all sides. It is now up to the readers and experts to conclude scientifically and technically the pros and cons of MTBE usage in gasoline. Thousands of studies, reviews, websites, and web pages are available on this subject, each providing a particular point of view. With all this information available, it is surprising that a survey aimed at answering these questions and summarizing the preceding experiences is not readily found. This book provides information not currently available from a single literature source. All the editors and contributors of this book are experienced in the study of MTBE, and each of them would have employed such a survey in his own research program if it had been available.