Madrid’s municipal transport company (EMT) currently operates a fleet of around 2000 buses. In response to emissions targets set by the City of Madrid, EMT carried out an open tender procedure for 165 buses stipulating that they must be; Compressed Natural Gas (CNG), CNG- hybrid or electric models EMT applied the second of three methodologies available under the clean vehicles directive (2009/33/EC), using award criteria to give preference to clean, energy efficient vehicles. Points were given for low fuel consumption, emissions of HC, PM, CO and NOx, noise pollution, in addition to low environmental impact substances and electronic components. The company finally purchased 23 CNG-hybrid buses and 142 CNG buses, meaning it now runs one of Europe’s largest CNG fleets. EMT advise fellow transport operators to stay abreast of the latest technologies and maintain regular contact with all relevant manufacturers in order to achieve the optimal solution, according to requirements.