This volume provides a comprehensive overview on the vast amount of literature on solidification heat transfer. Chapter one develops important basic equations and discusses the validity of considering only conductive heat transfer, while ignoring convection, in the large class of materials which make up the porous media. Chapters 2 to 4 deal with problems that can be expressed in plane (Cartesian) coordinates. These problems are further divided into boundary conditions of temperature, prescribed heat flux, and surface convection. Chapter 5 examines some plane geometries involving three-dimensional freezing or thawing. Problems in the cylindrical and spherical coordinate systems are covered in chapters 6 and 7. Chapter 8 is an introduction to solidification in porous media.Many of the applications have been directed to water/ice soil-systems, but it should be clear that the basic techniques and solutions can be applied to such diverse areas as metallurgy, biological systems, latent heat storage, and the preservation of food.