This book cleverly integrates the research on welfare measurement and social accounting in imperfect market economies. In their previously acclaimed volume, Welfare Measurement, Sustainability and Green National Accounting, the authors focused on the external effects associated with environmental damage and analysed their role in the context of social accounting. This book adopts a much broader perspective by analysing a wide spectrum of resource allocation problems of real-world market economies. The authors' aim is to derive exact welfare measures in imperfect market economies and compare them with their counterparts in a first-best equilibrium. Using numerical analysis, they also attempt to make the leap from theory to practical application by measuring the empirical importance of market imperfections. Such analysis provides the tools for examining whether 'real life' approximations of the welfare contribution of external effects, such as information collected by using the willingness-to-pay method, actually capture true and accurate values. Finally, the authors address the theory of cost - benefit analysis, in terms of environmental and other public policies, in dynamic general equilibrium models.