This book presents a mathematical development of a recent approach to the modeling and simulation of turbulent flows based on methods for the approximate solution of inverse problems. The resulting Approximate Deconvolution Models or ADMs have some advantages (as well as some disadvantages) over more commonly used turbulence models: ADMs are supported by a mathematically rigorous theoretical foundation. ADMs are a family of models of increasing accuracy O(δ2N+2), where δ is the averaging (or filter) radius.