The D.C. governmment, which earlier this year began offering one-stop shopping for most licenses and building permits, now is considering a plan to allow residents to purchase new license tags each year at the same time they get their cars inspected.

The plan, if approved, could sharply cut the amount of time thousands of city motorists spend in lines each year getting new auto tags and having their cars inspected.

Under the proposal, motorists who insist upon obtaining their new license tags in person, instead of by mail, could purchase them when they bring in their cars to one of the city's two vehicle inspection centers, according to Robert O.D. Thompson, assistant director of the Bureau of Motor Vehicle Services.

"The mayor is impressed with the one-stop shopping concept for citizens," Thompson said.

"We're trying to minimize the number of visits citizens must make . . . . The plan would also achieve the maximum use of D.C. personnel."

Thompson said the plan is being developed by a task force of the motor vehicle bureau and probably will be put into operation within a year, after the city's records of car inspection and registration have been combined within a new computer system.

"It's definitely coming," Thompson said. "We are compelled to slow up a little in implementing the plan until we advance our computer capability."

While the plan would cut in half the number of trips that motorists must make each year to comply with the District's motor vehicle laws, there was no way to immediately determine just how much time the plan would save the average motorist.

The city yesterday inaugurated a new system of staggered car registration that officials said ultimately would put an end to perennial long lines by assigning motorists specific months throughout the year to register their cars.

In the past, the city's 250,000 registered motorists were required each year to register their vehicles by March 31, a system that usually resulted in huge crowds outside city officies as the deadline approached.

Now, the registration will be staggered so that only a fraction of the city's motorists will have to register at any one time.

Yesterday, the city began issuing tags under the new system to motorists who were registering their cars in the District for the first time or who failed to meet the deadline for registration last March.

Car owners currently registered in the District will not be affected until February, when notices of registration renewals are sent out.

Motorists will be given registration certificates that will be good from three to 15 months, the first step towards staggering registrations throughout the year.

Motorists who prefer to register their cars by mail may continue to do so, city officials said.

Only 260 persons turned out yesterday at the main office of the motor vehicle bureau, 301 C St. NW, to purchase new tags, and officials said that operations went smoothly.

Christine DeSantis, a medical instruments salesperson, said she was pleased that it took very little time yesterday to register her newly acquired car.

"It was pretty fast," she said. "I've been here when there were 10 times as many people waiting in line."

Michael L. Lapadula, a general contractor, said the staggered registration system was "quite wonderful."

"I came here two weeks ago, and it was so screwed up I just grabbed some forms and left," Lapadula said. "This time, I thought it went really well."