Oil and gas are essential energy resources and have become more precious with the economic rise of China, India and Brazil. While consumption has risen tremendously, satisfying this demand has become more challenging and complex. With rising complexity and capital investment, quantifying the economic risk in developing existing and new fields has become paramount for raising shareholder value, and optimize resource allocation. The book provides an outline of the theory behind quantifying economic uncertainty for oil and gas projects, utility theory in the context of oil and gas projects and the increasingly important aspect of hedging against negative field development outcomes. Taking this into account, a novel optimization framework using option theory is introduced to improve project selection and enable practitioners to determine the optimal projects and their working interests for maximizing economic return.