Unconventional resources are those that have been bypassed by conventional oil and gas recovery technologies for decades, because they were not considered economically feasible to produce. The improvements in geophysical and geochemical exploration as well as drilling and completion technologies since the early 1990s have opened up vast new resources in the U.S. both onshore and offshore. This book is the only comprehensive treatment of these resources, covered in-depth by one of the most well-respected engineers in oil and gas today.