Mobility and increased access to transportation are two of the most important global forces for the alleviation of poverty. This is especially true in rapidly developing areas of the world, exemplified by China and India. It is also true in the United States, where huge gaps in mobility between rich and poor remain. Growing concern over the need to address global sustainability focuses attention on the rise in greenhouse gas levels, which is increasingly associated with increases in mobility. It is often suggested that improved mobility must be sacrificed to achieve sustainability. This paper examines the trade-offs between the need for mobility to foster economic development and the need to reduce the production of greenhouse gases to achieve global sustainability. The attainment of sustainable mobility requires increased global access to goods, services, education, and economic opportunity, alongside reductions in the production of greenhouse gases. The attainment of one cannot be an excuse for forgoing the other. Transportation technology and policy must address the twin goals of improving mobility while decreasing the levels of production of greenhouse gases.