The 4th European 'Transport Research Arena' (TRA) Conference, will be held in Athens, Greece, 23-26 April 2012, hosted by the Greek Ministry of Infrastructure Transport & Networks and supported by the main transport industry stakeholders in Europe: the Conference of European Directors of Roads (CEDR), the  European Commission (EC), the European Road Transport Research Advisory Council (ERTRAC), the European Rail Research Advisory Council (ERRAC), and the European Technology Platform Waterborne (WATERBORNE). TRA 2012 seeks to reflect the multidisciplinary nature of the transport sector and, for this reason, addresses all stakeholders in both the public and private sectors and all professionals, regardless of their roles (researchers, practitioners, designers, constructors, operators, administrators etc.).The deadline for submission of 300-word Abstracts is 15 April 2011