A writeup by The Atlantic Cities of a paper in the Transportation Research Board journal of the National Academies looking at the effects of parking on the vitality of urban centers. It’s found that the detrimental effects of dedicating urban real-estate outweigh the potential benefits of making it easier for drivers to access your central business district. Those cities that stopped adding parking to their urban cores after 1980 were found to have more jobs and higher incomes on average than those that continued adding parking.