Shoup has studied the issue of parking as a key link between transportation and land use. As a consultant to the U.S. Department of Transportation, he completed a report on "Cashing Out Employer-Paid Parking," which explains how employer-paid parking increases solo driving to work. As a remedy, he proposed that employers who subsidize employee parking should be required to offer employees the option to take the cash value of the parking subsidy if they do not take the parking itself. This proposal has since been passed into law in California, and the Clinton Administration has adopted the proposal as one of the legislative goals of its Climate Change Action Plan. Shoup is currently working on a grant from the California Air Resources Board to evaluate how cashing out employer-paid parking encourages ridesharing to work.

As a consultant to the World Bank, Shoup has worked on ways to finance public infrastructure in low-income neighborhoods. For example, his proposal for a new way to use special assessments to finance public services that benefit specific properties led to passage of California's deferred assessment legislation, which enables cities to use deferred special assessments to meet the public infrastructure needs of older neighborhoods.