In the frame of the co-decision, the European Parliament adopted in its plenary meeting on 13th December 2006, the compromise package on the Euro5-6 regulation. The text, which came out after several months of informal negotiations between the Parliament, the European Commission and the Council, has been forwarded to the Council for official approval. Publication in the Official Journal was mid 2007. The main features of the Euro5 standard for gasoline vehicles are a further reduction of NO(x) to 60 mg/km, introduction of NMHC and introduction of particulates limits for direct injection; however there was no real cost/efficiency of these measures; Diesel light vehicles have a drastic reduction of particulates (to 5 mg/km) and a reduction of NO(x) (to 180 mg/km). The standard will be mandatory as of 1st September 2009 for new M1 vehicle types and as of 1st January 2011 for all new M1 vehicles. The Euro6 standard will reduce further the NO(x) limits for diesel vehicles to 80 mg, without any exemption, which is expected to make specific DeNO(x) aftertreatment necessary. The dates of application start from 1st September 2014. For both standards, light commercial vehicles of class 2 and 3 have one additional year to fulfill their corresponding standards (which are slightly different). Fiscal incentives given by Member States are allowed, but only for the next stage (so no Euro6 incentives before 1st September 2009). The regulation also includes an obligation to give access to technical repair information and gathers other directives concerning smoke and measurement of fuel consumption. A number of 'details', which are in fact as important as limits and dates, were discussed under the 'comitology' process under the umbrella of CATP; the final vote of this committee were on 1st October 2007; the combination of the two documents describes the requirements of Euro5 and, with some 'details' yet to be defined, Euro6. This regulation will increase very significantly the cost and complexity of Diesel passenger cars and light commercial vehicles, possibly modifying the balance between market shares of spark ignition and of Diesel, at the detriment of fuel consumption and CO2 reduction. An 'In Use Performance Ratio' evaluating how often the On Board Diagnostic is performed is a significant new requirement. The information given here are the best we have, but check should be made once the official documents will be released.