In 1979, Japan issued the Energy Conservation Law, or Law on Rational Use of Energy. Based on this law, Japan issued a set of building energy standards for commercial and residential buildings called the Criteria for Clients on the Rationalization of Energy Use for Buildings (CCREUB).Two standards apply to residential building: 1) Design and Construction Guidelines on the Rationalization of Energy Use for Houses (DCGREUH), issued by the Ministry of Construction in 1980 and later revised in 1992, 1999, 2003, 2006 and 2008; and 2) Criteria for Clients on the Rationalization of Energy Use for Houses (CCREUH), issued by the Ministry of International Trade and Industry and the Ministry of Construction in 1980 and later revised several times between 1992 and 2008. Compliance with these standards is voluntary for most buildings, although Japan has recently adopted penalties for non-compliance that blur this distinction."