This book presents a rigorous mathematical development of soil water and contaminant flow in variably saturated and saturated soils. Analytical and numerical methods are balanced: computer programs, among them MathCad and Fortran, are presented, and more than 150 practice and discussion questions are included. Students are thus exposed not only to theory but also to an array of solutions techniques. Those using the book as a reference will appreciate the careful development of basic flow equations, the inclusion of solutions and methodology currently available only in journals and proceedings volumes, and the examples and calculations directly applicable to their own work.