For the fifth year running, Fiat is the "greenest" car company after recording the lowest level of CO2 emissions by vehicles sold in Europe in 2011 with an average measurement of 118.2 g/km (4.9 g/km less than the 2009 average).
The test measures the total CO2 emissions of every car sold by each car maker, rather than one or two vehicles in a range and their individual figures.
The test's independence is certified by JATO Dynamics, an automotive consultancy and research firm.
Fiat also ranked first as Group, with 123.3 g/km, an improvement of 2.6 g/km on last year, a remarkable achievement considering this includes supercar brands Ferrari and Maserati.
This is an important achievement and a continuing improvement: over the past five years, Fiat has reduced its average emissions by 14 per cent, from 137.3 to 118.2 g/km of CO2 - significantly lower than the target, 130 g/km, set out by the European Union for 2015.