This paper describes the establishmentof the Rural Access Index, one of several Transport HeadlineIndicators endorsed by the World Bank Transport Sector Boardin 2003. The index has been adopted for the ResultsMeasurement System (RMS)2 of the 14th round of theInternational Development Association (IDA-14) which waslaunched in July, 2005. The Index was developed in responseto the consensus led by borrowers that it identifies animportant priority for poverty reduction strategies in viewof the established links between physical isolation andpoverty. This provides stronger linkage to the MillenniumDevelopment Goals (MDG) and better assesses the contributionof IDA assistance to the sustainable development of thebeneficiary countries. The Rural Access Index provides aconsistent basis for estimating the proportion of the ruralpopulation which has adequate access to the transport system.