Take a client perpetually stressed out. Add a perpetual shortage of money. Throw in anxious state and local politicians watching your every move and the years that can pass before your ideas are carried out. That sums up Young Ho Chang's job as Fairfax County's transportation chief.

Chang, who announced last week that he was leaving the county government on July 8 after six years to return to the private sector, reflected on how his leadership over the road and transit network of Washington's largest suburb became "the best job I ever had."

"You're in the middle of everything," said Chang.

Chang, 41, who goes by the first name Ho, is returning to ATCS, a Dulles engineering and planning firm, this time as senior vice president overseeing federal and state contracts and the company's work for private developers. He called the move "a great opportunity." For the first year, ethics rules will prevent Chang from working on any project that he was involved in while on the county staff.

He'll arrive battle-tested. In a county where traffic jams are an unhappy way of life and growth in jobs and residents keeps congestion coming, Chang has had a hand in planning or executing more projects than most transportation planners can dream of. A rebuilt Woodrow Wilson Bridge, the Springfield Interchange, a Metrorail extension to Tysons Corner and Dulles International Airport, a growing Virginia Railway Express, an expanded Fairfax Connector bus service, Beltway high-occupancy toll lanes -- he has worked on them all. Not to mention speed humps and other traffic-calming measures, the red-light cameras now in their twilight and thousands of improvements to roads large and small.

"We've taken a lot more ownership of projects getting done," he said. The Virginia Department of Transportation builds, maintains and operates most of Fairfax's roads, but the county has used bond money to build some of its own, such as the Fairfax County Parkway.

Adding to the job's high profile, Chang has had to navigate among often-warring constituencies: pedestrians, bike riders, commuters, state officials, Metro officials, federal officials and politicians from Fairfax to Richmond who want to see progress yesterday.

"Transportation is very complicated," Supervisor Sharon S. Bulova (D-Braddock) said, noting the field's "complicated processes and mixture of funding streams."

"Ho is great at explaining transportation issues to people who are not professionals," she said.

Chang always stayed cool as he faced angry crowds at public hearings on projects the public either didn't want or wanted faster.

He redefined the department's role to encompass what planners call a multi-modal focus: That is, for instance, plans for new bus service now must take into account whether crosswalks, traffic signals and bus-only lanes are in place.

Another priority was seeing through road projects whose plans were yellowing next to other designs for other projects. "The key is getting the project done, not funding more planning studies," he said. Two cases in point: the widening of Centreville Road and of Route 29 at Gallows Road, two long-delayed projects, are now moving forward.

Chang said he is pleased that Fairfax Connector, the county-run bus service, "is in a better place than it was six years ago," with about 8 million riders a year, up from 6.5 million.

There were, of course, low points. The failed proposal for a sales tax increase in 2002 was the low, he said, because it denied the region a reliable stream of money for road and transit improvements.

"We would be in a very different place if it had passed," he said. "We're just working around the edges now." Like many colleagues, Chang blamed a failure to "package and explain" why voters should approve raising the sales tax.

Chang notes the high point of his tenure with pride: an ongoing $55 million transportation face-lift that's bringing major improvements to bus service along Route 1 (Richmond Highway), overhauling routes and schedules, and enhancing pedestrian safety.

"This is stuff you can point to and say, 'This is just the beginning, folks,' " he said. "People want to see things. They don't just want to see architectural renderings."

Young Ho Chang, outgoing county transportation chief, at Fairfax County and Fair Lakes parkways. He said his job put him "in the middle of everything."