This monograph is devoted to the development of value theory of computable general prices in cost-benefit analysis under fuzzy rationality. The book demonstrates the use of fuzzy decision algorithms and logic to develop a comprehensive and multidisciplinary cost-benefit analysis by taking advantage of current scientific gains in fuzziness and soft computing. The theory is developed at a basic level of microeconomics leading to aggregation in fuzzy decision environment composed of subjective phenomenon, imprecision, approximations and problems of information elicitation. The book integrates the theories of computable prices, fuzzy decisions and social decision-choice processes into a set of decision algorithms accessible to practitioners, researchers, graduate students, and policy makers in economics, engineering, as well as physical, social, and medical sciences. It brings into focus the fuzzy mathematical theories of computable equilibrium prices, social discount rate and cost-benefit criterion on both micro and aggregate levels and how they relate to revealed preference, contingent valuation and hedonic pricing methods. Additionally the monograph covers computational problems of optimal taxation, cost-benefit distributions, social goal-objective formation and rent-seeking activities as fuzzy processes.