Since the discovery of plate tectonics, impact cratering is arguably the most significant geologic process now recognized as an important process on Earth. Impacts into ice, another main topic covered in this book, may be important on other worlds. Large numbers of impact craters that formed in marine environments on Earth have only been discovered in the last 10 years. Twenty-five craters that formed in marine environments have been documented, according to the first chapter of this book, although none are known that excavated oceanic crust. The papers in Cratering in Marine Environments and on Ice will whet your appetite for the exciting and ambitious range of topics implied by the title, which stems from a conference in Svalbard, Norway, in September 2001. This book provides a flavor of the rapidly advancing and diverse field of impact cratering.