It is dawn and cold on the dingy, trash-strewn street barely a mile from the White House. Despite the early hour, the street is busy. Men bundled in thick jackets and ski caps stand along the curb gesticulating strangely at slow-moving cars and chanting, "Bam-D, Bam-D, Bam-D."

It is the incantation of drug dealers, the inner-city invitation to passing motorists to buy illegal drugs. The words change from street to street, but the chant remains. Here the men are selling "Bam" -- a power-packed powder known more formally as phenmetrazine and used to prolong the heroin "high" -- and "D," or Dilaudid, a pill used as a heroin substitute.

The scene is the 900 block of O Street NW, a rumpled ribbon of concrete tucked away in the heart of the Shaw inner-city area. It is one of the city's toughest and most notorious drug-dealing centers. It is also one of the deadliest blocks, according to the D.C. police department.

Disputes among dealers and customers erupt periodically in gunfire. At least four fatal shootings have occurred there since May. The block is crisscrossed by a spider-like network of alleys and narrow streets that provide an instant refuge for the dealers when the police patrols appear.

In other neighborhoods in Shaw and around nearby Logan Circle, older residents and newcomers band to oust drug traffickers. But many residents of O Street and adjoining Columbia Street simply have accepted the drug phenomenon as part of their lives and make no attempt to dislodge the dealers and their cohorts by calling the District Building or police.

This acceptance comes from a live-and-let-live philosophy practiced by many residents. But there is also some pragmatic fear of possible retaliation by drug dealers if the status quo is disturbed. Maintaining the status quo buys protection and an odd kind of stability for the block.

"At first, I called the police," said one man who asked not to be identified, "but then my house was broken into, and they bombed the front door. So now I don't call the police, and they don't bother me. You have to be very careful here."

"It's just part of living here," said Kate Roach, a two-year resident of the block and a strong supporter of her neighborhood. "It's kind of like selling apples and oranges. It goes on all the time."

"Drugs are the order of business here," said Ulysses Grant Cook as he moved his furniture into a renovated three-story apartment at Columbia and O streets this month. Cook's new home is one of very few renovated buildings on a block of mostly boarded-up Victorian houses.

The intricate geography of the block, with the labyrinthine Naylor Court alley on one side and tiny, one-way Columbia Street on the other, provides a natural shelter for dealers and gives customers easy access and quick exit.

The dealers station themselves at both ends of O Street and at the two entrances to Naylor Court. They hail passing motorists with complex finger signals to indicate what drugs are available. If drivers are interested, they pull over to the curb and a deal is made.

Like the O Street residents, the police appear largley resigned to the status quo.

"You have that little, closed area, and it's a fine little fortress," said D.C. Police Lt. Ronald Harvey, head of drug enforcement for the 3rd District. "They see us coming before we get there."

Describing the dealers as "self-employed businessmen who work at home," Harvey said, "It's just like selling real estate. It's a business. You have to remember that these are people exsisting like anyone else. But they have a need to escape, and they use drugs. He [the dealer] goes around the law to find a little money."

The laissez-faire atmosphere of the street extends even to the usually energetic Logan Residents Association, which considers the 900 block of O Street part of its neighborhood.

"We have not been as aggressive in dealing with drugs as with prostitution," said Sherrie Black, president of the group. "It [drug dealing] is a reality, but I cannot believe anyone likes it. You build up a tolerance, like with a toothache, and you learn to live with it. But it's not a pleasure."

Learning to live with it has, in some cases, built delicate bridges between the world of the dealers and the world of the residents. Several residents know the dealers by name, and they hail each other en route to work in the morning and coming home at night.

The dealers occasionally are solicitous and even protective of the residents -- a sort of trade-off for the acceptance of the status quo.

Roach, who was held up at gun-point outside the neighborhood recently, walked home that night as usual. "One of the dealers walked up to me," she recalled, "and said, 'We heard what happened. I'm glad you weren't hurt.'"

A reporter watching Columbia and O streets for several days recently observed dealers and customers openly negotiating while life in the neighborhood went on. Women pulled their grocery carts to the nearby Giant grocery store. Children played football in the street. A mailman wended his way among the dealers.

Most of the dealers are black young men. Most of the customers are whites, many driving cars with Maryland and Virgina license plates.

The dealing, the negotiating, the buying and selling go on day and night, a seemingly endless cycle of cars entering and leaving the block. To the casual visitor, it appears bizarre. To Roach, a vibrant, cheerful woman, it is the normal life of O Street.

"This is my home," she says. "I live here. I tell all my visitors to ignore the friendly people on the street and just keep saying, 'No, thank you.'"