This book is the comprehensive summary of 20 yr work by Canadian researchers. Following an introduction, chapter two introduces the properties of ice and snow providing a fundamental background for understanding the abilities and limitations of remote sensing technology. The eleven individually authored chapters that follow have been structured to connect early experiments to present capability, and to detail surface (acoustic) sensing techniques upwards through to satellite systems. From simplicity to complexity, remote sensing techniques progress from passive to active systems, from long wavelength systems to short, and from rudimentary laboratory apparatus to satellite systems. Chapter 13 concludes with a discussion of supplementary topics and future directions. -H.R.Goode