The book describes the structure of Keynes-Leontief Model (KLM) of Japan and discuss how the Japanese economy could overcome the long-term economic deflation since the mid-1990s. The large scale econometric model and its analysis have been important for planning several policy measures and examining the economic structure of a country. However, it seems that development and maintenance of the KLM would be very costly. The book discusses how the KLM is developed and employed for the policy analyses.