ADB's existing areas of transport operations, focusing mainly on roads, will remain relevant in most developing member countries in the next decade. While previous ADB projects and transport sector road maps (within country partnership strategies) have addressed some dimensions of sustainable transport, few have done so comprehensively, and there have been gaps and blind spots.

For example, some past projects aimed to reduce transport costs and increase vehicle speeds without considering how to avoid some of the adverse impacts this might bring, such as increased road accidents, noise, and emissions. Some projects sought to make long distance transport more accessible and affordable but did not improve rural roads and bus services or provide facilities needed for women’s use of transport. Some projects emphasized cost recovery to support financial and asset sustainability but did not ask if tariff levels were affordable or whether subsidies were justified for some groups.

In the future, mainstreaming sustainable transport will involve giving attention to all the elements of sustainable transport, and finding the best balance between them in order to develop transport systems that are accessible, affordable, safe, and environment-friendly.