OLOKWANE, South Africa — It is a wilting summery day on Grasmere Grove, with sprinklers splashing the red begonias, barefoot boys hopping across the sizzling sidewalk, and windows flung wide open to snare the elusive breeze.

At No. 18, the doorbell is ringing. The gray blinds flicker and Marissa Potgieter peers out anxiously. Then she breaks into a smile and her front door swings open.

"What's news?" asks Mrs. Potgieter, grinning at her neighbor, Ntshole Mabapa. "I'm broke," jokes Ms. Mabapa, a lawyer who recently started her own management consulting firm.

Mrs. Potgieter's little girl, Chene, dances in the doorway, showing off the gap where a baby tooth used to be. Soon, the women are sitting in Mrs. Potgieter's parlor, chatting about the tooth fairy and the heat.

It is a typical suburban tableau. Except that this is South Africa and Mrs. Potgieter is white and Ms. Mabapa is black.

Eight years ago, such a casual exchange was almost unimaginable in this conservative town, about 160 miles northeast of Pretoria, and it is still rare. For decades, blacks were barred from buying or renting houses in white communities and were forced to live in ghettos and rural villages. But with the end of apartheid in 1994 and the emergence of a black elite, South Africa's white suburban neighborhoods are slowly integrating.

The mingling has stirred a cautious shift in how some people view their neighbors. Whites who have been taught that blacks are inferior and blacks who view whites as enemies are learning to live side by side, even if considerable mistrust remains.

Most blacks and whites still live separately, as they have for generations. But census data show that in the early 1990's, South Africa began to desegregate, and demographers believe that data from the 2001 census, to be published next year, will show that the pace has quickened in recent years.

The shift is particularly notable in provincial capitals, like Polokwane, where the number of black professionals — politicians, business executives and consultants — has surged. Today, Grasmere Grove, a cul-de-sac of tidy middle-class homes, offers a glimpse into this quiet social transformation.

Nine white families, eight black families and one mixed-race family share this block of one- and two-story homes and tend to its green lawns, skittering dogs and yellow roses. A white fireman and several black government officials live there. There is also a black traditional healer and both black and white company managers.

Many people prefer to keep a polite distance. But some are reaching out. The Potgieters and the Mabapas, for instance, wave to each other when they drive to work or run errands. Ms. Mabapa, 35, who lives at No. 21 with her mother and her 12-year-old nephew, stops by to admire the new paint on the Potgieters' house.

Mrs. Potgieter, 33, and her husband, Johan, offer to help when Ms. Mabapa's friend's car breaks down. And both families like to gossip now and then about the neighbors.

Yet the two families rarely socialize in each other's homes, and they seldom discuss politics. The Potgieters frown on interracial marriages, and Ms. Mabapa says she has had only one close white friend.

It is sometimes difficult to find common ground, particularly because Ms. Mabapa is optimistic about her future while the Potgieters remain uncertain about their prospects under the black government.

The casual friendship represents a significant change, and at the same time shows how far South Africa is from closing the gap between blacks and whites, even those with similar earnings living side by side.

"When we bought here, people said, `You're living next to blacks? Why?' " recalled Mr. Potgieter, 47, who runs a construction company. "I said, `I don't have a problem. They're people like us.' "

"The black-white divide is still there," he said. "We were separate for too long. Our traditions are different. There was so much hate. But this is South Africa. We need to try to get this cross-cultural thing going."

The apartheid government tried to ensure that integration would never happen. Blacks were segregated during British colonial rule, but it was the Afrikaner government that turned racial separation into national policy.

After winning power in 1948, Afrikaner officials forcibly removed three million blacks from the cities and dumped them in overcrowded, dilapidated townships and remote rural communities.

In 1951, 69 percent of South Africa's black population lived in specifically designated neighborhoods. By 1991, the year that residential restrictions were scrapped, the figure had grown to about 91 percent, according to A. J. Christopher, a demographer at the University of Port Elizabeth.

In 1991, only about 7 percent of South Africans lived in integrated neighborhoods. By 1996, the figure had increased to about 12 percent in provincial capitals. Experts believe that the country has become significantly more integrated in recent years as the number of wealthy blacks has increased.

"Suddenly there are substantial numbers of black people who can afford to buy houses and move into what had previously been white areas," Mr. Christopher said. "Even though these towns would still be considered extraordinarily segregated by American standards, this does represent a major change."

In February 2000, Ms. Mabapa moved into her three-bedroom house on Grasmere Grove. In April, the Potgieters moved in across the street. Ms. Mabapa was the first person to welcome the white family to the neighborhood.

"I didn't think I would ever live with whites; it was unthinkable, I suppose," Ms. Mabapa said, as she settled onto her cream-colored sofa to consider the changes in her life. "So much has changed."

For a woman who grew up in a cramped black township, her spacious house on this integrated block is the most tangible symbol of that change. African vases adorn her shelves, and a computer hums in her home office. A maid comes by to cook and wash Monday through Friday.

Ms. Mabapa, the daughter of a barber and a tavern owner, recently opened a computer-training center, and she drives to her office there in her Toyota Corolla. Her mother, who raised two daughters in a four-room house, feared and avoided white people.

Ms. Mabapa works and lives comfortably among whites. She admires Mrs. Potgieter, who cooks and cleans without a maid, which is unusual in white middle-class communities. ("She's the hardest-working white woman I've ever seen," Ms. Mabapa said.)

She admires Mr. Potgieter, who holds his wife's hand whenever they walk around the neighborhood. ("If I found a man like that, maybe I'd get married," Ms. Mabapa said wistfully.)

And she has discovered that two other white women on Grasmere Grove like to sew and paint on fabric just as she does.

"When we were growing up, you didn't expect to have white people as friends," Ms. Mabapa mused. "I've grown to believe you can have white people as friends. It's difficult, but it's possible."

Across the street, Mrs. Potgieter answers the door when the bell rings. Without thinking, she greets her visitors with the double handshake favored by black South Africans. "I'm so used to greeting them now," she said.

Mrs. Potgieter grew up on a farm where the racial lines were clear: whites were landowners and blacks were laborers. Her husband's family fled to South Africa from Kenya when blacks took over the government there in the 1960's. But he said he sympathized with black South Africans, because he himself grew up poor.

"They got a raw deal," he said.

Still, he and his wife accepted the apartheid system. Like most whites, they adopted the language of the white government and referred to antiapartheid activists as terrorists. But after apartheid ended, the Potgieters decided to adapt.

Mr. Potgieter visited Robben Island, where Nelson Mandela, the country's first black president, was imprisoned for 18 years. Their children have black friends on Grasmere Grove, and the Potgieters recently allowed their 9-year-old son to visit a reptile sanctuary with a black family.

The couple even brought a black acquaintance to their predominantly white church.

"I drive a green BMW, but it might as well have been red that day," Mr. Potgieter said, chuckling. "Everyone was staring."

Such friendliness is still viewed with some suspicion. One white neighbor questioned the Potgieters' decision to bring the woman to church. Some relatives, who live in exclusively white neighborhoods, criticize the Potgieters for mixing easily with blacks.

Mrs. Potgieter tells them that the blacks on Grasmere Grove are different from the uneducated laborers she grew up with. "They're fantastic people," she said. "Look at these houses. Even the blacks, their houses are nice and tidy. You can eat off the floors."

Yet the Potgieters have repeatedly declined invitations to visit their black neighbors' homes. The trouble, Mr. Potgieter said, is that blacks are still too different. He says that one black neighbor grows corn and slaughters chickens in his back yard and that others still eat traditional African foods, like cornmeal porridge.

"Lovey, we've taken them out of the bush, but they still have the bush in them," Mr. Potgieter explained to his wife, who nodded. "They like to be linked to a white person. It's a prestige thing.

"But the black, his communication is not the same as ours," he said. "The level is not the same as ours."

Mr. Potgieter does not share his feelings with his black neighbors. But Ms. Mabapa is keenly aware of the lingering unease between blacks and whites. When she gave a housewarming party, she decided at the last minute to invite her black neighbors but not her white neighbors.

Black people, she reasoned, would not mind being invited to a social function without much notice. She thought the Potgieters might take offense at receiving an invitation the day before the party.

"We're still very careful with each other because we're still not sure," Ms. Mabapa said. "As black people, we don't know if white people have really accepted us. White people don't know if we've forgiven them or not.

"People haven't taken the time to know each other yet," she said. "It's only just beginning to change."