The future of Tysons Corner remains one of the greatest uncertainties facing Fairfax county, with Metrorail and a flurry of redevelopment projects expected to profoundly reshape the area in coming years.

One pre-eminent expert in city planning believes Tysons, if done right, could “mimic much of the success” of Arlington’s Rosslyn-Ballston corridor, where walkable neighborhoods, mixed-use development and manageable traffic have won accolades across the country as a victory of smart planning.