Roy Guyther is a chunky man with a beaming, harmless smile full of get-up-and-go. There is about his demeanor something of the small-town mayor, which he isn't but which he probably could be if he wanted. Guyther's handshake is dry and firm, thick-fingered, like those of the farmers around here. And, like the farmers, he is close to the earth.

Right now he is standing on that earth, at the side of the road, waiting to cross the stretch of asphalt that separates his home from his office, checking each direction for traffic.

For a moment, Guyther looks disgusted. "not so long ago I didn't even have to check for cars," he says, snorting. "I just crossed the street. Now I have to wait for them. I'm like most of the folks down here who resent people who've moved in. I'd rather have the rural county."

Standing there fidgeting, smiling that harmless smile, with his glasses glittering in the sun, he looks rather like a president of the local Lions Club, which he used to be. He does not look like the doctor, which he is.

The road clears, and Roy Guyther crosses it.

St. Mary's County in Maryland is south on Route 5, through Prince George's through Waldorf, and past the market where Amish farmers sell cattle, pigs, horses, ponies, goats, rabbits, ducks and chickens.

It is through Hughesville, past the almost-half-mile unbroken stretch of tobacco warehouses, past the general store where a sign in the window reads, "Card Game Sunday Mitchell's Bar Everybody Welcome," and where on an outside stoop out-of-work folks sit at 10:30 in the morning, already drinking.

And that isn't yet St. Mary's County. It's still south from there, down to Mechanicsville.

Guyther is at home out here, with the fields of tobacco and the fishermen and crabbers who work on the water. He grew up in a house on the spot where his office is now. He delivered newspapers, too, before he went away to the University of Maryland for college and medical school, before he came back 31 years ago to open an office.

The office Guyther shares with a young physician, Robert Bauer, includes a small laboratory and a technician. Patients sometimes wait there for test results. There's a hitching post in the parking lot for Amish buggies.

From this setting, Guyther, 60, has known various forms of fame. Last year the American Academy of Family Physicians, in conjunction with Good Housekeeping magazine, named him "Family Physician of the Year."

But there are other measures of success.

In one restaurant on Route 5, everyone knows Guyther.

"I was his patient, honey," says the waitress. She switched doctors eight years ago, when Guyther gave up his practice for a year to teach full-time at the University of Maryland School of Medicine. (He still teaches there one day a week.)

In the kitchen, the cooks know him. The older one nods -- Guyther was her doctor until he referred her to another doctor. Of the 23 physicians in the county, Guyther recruited seven and helped set them up.

The younger cook seems embarrassed. She smiles shyly, blushes and says, "He delivered me."

Guyther is of this community. His experience goes beyond the medicine. He makes house calls -- a practice as rare in the country as it is in the city.

As he drives around, pointing to that man on the tractor who . . . or that house where Mrs. . . . or to the place over there where when he was a boy he --- as he does that, it's as if it's all his, this county. All of it.

Guyther's voice, no matter how soft it is at times, carries with it the authority of a man of substance. He subscribes to three newspapers, The Wall Street Journal, The Washington Post and The Baltimore Sun. He is past president not only of the Lions Club but of other local groups. He is an eminent figure in this town.

"I know Roy," says a mechanic, half-bitterly and half-cynically. "I see him driving around in his Mercedes."

Guyther drives a Pontiac, not a Mercedes; it is perhaps his prominence and aura of authority that the mechanic resents.

But an air of authority, while it can produce resentment, also can bring benefits.

Once, one of Guyther's patients had barricaded himself in his house with his family and a gun. Sheriff's deputies surrounded the place ans asked for Guyther's help. Guyther approached the door.

"I said, 'I'm sorry you're upset, and can you give me your gun?' -- and he did," Guyther recalls. "I knew him. I didn't think he would hurt me."

There are less-dramatic examples of Guyther's authority, such as when he says to a patient, "Will you call me Thursday?" Both he and the patient know that is not a request. The patient will do it.

Some types of authority are won through intimidation, some types through achievement and some through trustworthiness. The people out here trust Guyther. They want to offer up to him their problems. Like people in other situations who willingly bow to authority, they want him to take care of them and tell them what to do. To help them. Heal them. h

It is a Tuesday night. Guyther sits inside his office, alone. The lab technician has gone home. Bauer has gone home. The cleaning lady has gone home. Half the lights are off and the office air is thick with the smell of disinfectant.

Five local doctors take turns keeping their offices open at night and on weekends, not for emergencies -- St. Mary's Hospital in Leonardtown is only 13 miles away -- but to provide routine service. Tonight is Guyther's turn.

"We do it because we think it's important for the continuity of care," Guyther says. Also because, even out here, the base rate at the emergency room is $60. Guyther says he charges no more than $15 for typical office visit, adding, "A lot of these people don't have health insurance."

A young girl is running a fever. She is frightened and uncomfortable, but Guyther's touch soothes her. He conducts a few tests, retreats to his laboratory and prepares a slide for the microscope.

"A lot doctors would debunk this," he explains almost apologetically. "A doctor looking through a microscope? But it goes with continuity of care, too."

Most of the people are not his usual patients, but he knows them anyway. Of a man with a back injury, he asks, "You're Billy's brother, aren't you? How's his blood pressure? We'd better check yours, too"

To one woman he says, "Were you a Davidson before you got married?"

"No. I'm Jeb's daughter, Grell."

Right, right. He nods. The Davidsons and the Grells; cousins. Now he's placed her. "Didn't I deliver someone in your family?"

"Yes, you sure did -- my sister."

He is different now, at night. During the day, with nurses and receptionists and a technician around, he is more caught up with the profession. He is friendly, all right, but it seems as if it's his business to be friendly then, and he is patronizing to people. At night, alone with the ill, the essence of what might be called his ministry comes to the surface.

A desperately ill woman suffering from Parkinson's disease sits in the waiting room. Guyther is surprised she has come, for usually he sees her on a house call. But this visit is for an emergency. She's having trouble swallowing and breathing. Her husband half-carries her inside the examining room. She cannot weigh more than 80 pounds. She cannot make the sounds of speech.

When Guyther asks questions, he asks them of her husband, not of her. They have been through this before. Even though Guyther cannot even speak with his patient, he seems most attentive to her. Her eyes signal want . As he talks, he meets that need. Somehow. And when she grows agitated, he rests a gentling hand on her forehead.

"Relax," he says. "Relax, now."

Despite all appearances, Guyther is not a simple country doctor. There is an element of hype. When a reporter calls, he answers the phone with a familiar, "Roy Guyther." With patients, he calls himself "Dr. Guyther." With some eagerness, too, he offers to get together his news clippings.

The "Family Physician of the Year" award that Guyther won is somewhat of a hype as well. John Mack Carter, editor of Good Housekeeping dreamed it up three years ago and suggested to Bill DeLay, public relations director of the American Academy of Family Physicians, that giving the award would be mutually beneficial.

"Obviously, we would be interested," DeLay says. "The magazine reaches so many people" -- housewives -- "who make health care decisions."

Guyther was a natural choice for the award. He has served on the boards of a dozen medical organizations, as president of the Maryland chapter of the Academy of Family Physicians, and on several governor's commissions and a presidential commission on employing handicapped people. Plus, he makes house calls -- which is always great public relations.

After Good Housekeeping's editors chose Guyther for the honor, the magazine's book division sent him their just-published medical encyclopedia. He liked it, and was sent on a national tour to promote it.

Guyther made four radio and TV appearances during one day in Washington, 16 appearances during a three-day stop in Chicago and Minneapolis, then went on to Los Angeles and San Francisco. In addition, he recently went to Boston for a medical seminar -- on how doctors should handle the media.

"He was a wonderful spokesperson for the book," says a woman with the public relations firm Good Housekeeping hired to promote it. "The book moved very well in terms of sales."

In addition, Guyther doesn't mind being known as a "specialist." The Academy of Family Physicians 10 years ago set up a board to certify family practitioners as specialists, just as surgeons are certified as specialists.

Guyther tires, not very successfully, to differentiate between family practice and general practice, and says a certifying board "does raise the status (of a family practitioner) a little bit, compared to the GP, who's the low man on the totem pole."

So Roy Guyther isn't quite so simple as he seems. He likes the attention, likes the recognition. So big business, PR firms and media hype have made their way out to S. Mary's County. Why shouldn't they? The folks out here have TV, too, just like the people in the city.

Washington is spreading out to St. Mary's County. Its suburbs encroach.

If big business, PR and TV can reach out here, so can the city -- or, rather, the forces of urbanization. These forces are making St. Mary's seem like everywhere else. They are changing rural areas. They are changing rural medicine, too.

"Folks out here used to make their living on the land or on the water," says a man in a Route 5 restaurant. "Now, if it wasn't for Pautuxent (naval base), hardly anybody down here would be working."

Another man adds, "Used to be, wasn't a Safeway store, wasn't a Western Auto out here. Just barrooms. Barooms every damn place you'd look. There's a hell of a lot less farms here, too. Folks built houses on 'em."

Along with the houses, they've got their Safeways. They've got their Jeans USA and their H & R Blocks. Maybe the changes aren't for the worse. Maybe it's only romanticizing to wish farms would stay farms. Maybe Safeways are better than barrooms. Maybe.

But it is not romanticizing to wish that the ways of rural medicine wouldn't change. Guyther's parking lot is of dirt -- the same dirt that the farmers plow -- not asphalt. The only asphalt in Mechanicsville is the lot by the volunteer firehouse. Government money.

But more asphalt is coming, and so are new young doctors. They'll probably be good doctors, but they won't be Guyther.

It's not just that Guyther makes house calls and the young ones don't. It's more than that. Even something as simple and basic as being willing to perform small surgery on a patient, even that's changed. Bauer, once a student of Guyther and now an office-mate, doesn't like to use a knife. At all.

"No, I don't do that," Bauer says. "Most of the younger guys don't. Take moles off and things? It's too much of a hassle. They complain they don't like the scar. You know."

So Bauer's patients see Guyther or a surgeon, even for the little things.

There are other differences. In one day, 80 patients came to the office. Bauer saw 50. Guyther, even working at night, saw 30.

Roy Guyther is one of a dying breed. But then, he thinks death is no enemy, that death, too, has its place. He still fights it, though. He's been fighting it for 31 years.

Sometimes death or the threat of death wearies him. Like when he sees a certain old friend once more in his waiting room. Guyther sighs then, his shoulders sag for an instant, then they straighten as if he knows he's beat, but he's not going to quit. And he calls softly to his friend.

"Hello, William. Come in."

He does not ask, "How are you?"