For now it is just a vacant lot in one of the more affluent sections of this black city, but in a few months Wellington Mnikati hopes to build a new house here.

The house should have been the fulfillment of a dream -- Mnikati designed it himself, and it will have a two-car garage, a bedroom for him and each of his three children and a study. But Mnikati's dreams are too big to fit into the confined world of Soweto and the small slot fashioned for blacks like him by South Africa's system of racial segregation called apartheid.

He wants the freedom to escape the ghetto and live wherever he can afford to on the substantial income he earns as the highest ranking black executive at Rank Xerox's South African corporate headquarters. He wants to send his children to integrated public schools. And he wants to be able to vote for those who determine his taxes and his future.

Most of all, he wants to escape the enforced inferiority of being a black man in a world where whites wield virtually total control.

"You may be a senior manager at Rank Xerox," Mnikati said, "but no matter how successful you may appear, at the end of the day you're black, and they don't miss a chance to tell you you're black."

Mnikati is one of a small but growing number of blacks to have made it in the white man's world. Middle-class, politically moderate and sophisticated, he is among those whose support South Africa's white-ruled government must capture if it is ever to fashion a workable deal over the country's future with its black majority.

Although he is proud of his personal achievements, Mnikati is far from satisfied with the pace of change in this country. He is deeply angry over the injustices he and his family suffer daily, is deeply worried about the future, and fears that his own position will grow worse as time passes.

That anger and fear, which he shares with the vast majority of his fellow urban blacks, help explain why the government's new proposals this week on restoring citizenship for blacks and abolishing restrictions on urban movement have done little to narrow the yawning gap between white "reforms" and black aspirations.

"As far as I can see, it means I get to have a passport, and that's where it ends," Mnikati said. "We still won't really be South African citizens. Citizenship means certain responsibilities and rights. But South African President Pieter W. Botha has made it clear we are not going to have any say in the administration of this country."

He said he fears that the end of "influx control" will only create more slums because the government will not construct the new housing needed for the flood of black migrants from rural areas. "There will be too many people chasing too few houses," he said. "Then the whites will turn around and say, 'I told you so.' "

In many ways Mnikati could pass for a successful executive anywhere in the world. He wears dark business suits to the office and on weekends switches to jeans and sometimes a "Team Xerox" sweatshirt. There are two cars in the driveway, a Toyota Cressida supplied by the company and an Audi for his wife. A video cassette player dominates the living room.

But there are crucial differences between Mnikati, 41, and the white world within which he operates. He is required by law to reside in segregated townships such as Soweto. Although he has lived in urban areas all his life, he must carry at all times his "passbook" entitling him to live here and to work in "white" Johannesburg or face jail and a fine.

The most important differences concern his children, aged 12, 9 and 6. By law they must attend the segregated public schools where much of their education is in a tribal language rather than the English they will need to advance in the increasingly sophisticated business world they will face after graduation.

Even the government concedes that the education in these schools is inferior to that of whites. To try to close the gap, Mnikati takes his oldest daughter Dipuo to Johannesburg each Saturday for private English and math lessons. He could send the children to integrated private schools, but tuition is high, he said, and the schools are too far away for the children to live at home.

Disruptions caused by a year of political violence have compounded the problem. None of the children wears the uniform to school these days for fear of being assaulted on the street by young activists enforcing school boycotts.

Tear gas was lobbed into Dipuo's schoolyard a few weeks back by soldiers enforcing regulations against students "loitering" outdoors. Some days the schools are closed without notice, and the children have to make their way home unescorted. Mnikati lives in fear that they will be picked up by police and arrested, as more than 1,600 students have been in recent weeks.

"From day to day you're never too sure," he says. "When you get home at night and they're all there, you heave a sigh of relief."

The only whites his children see regularly are the soldiers patrolling Soweto in armored vehicles, and Mnikati said he worries that his children will grow up hating whites and fearing them. He tries to teach them that whites are people like they are and that they should not hate nor feel inferior. At the same time, however, he knows whites can hurt his children, stifle their future or wreck their self-esteem. "Sometimes I wonder if I am making a mistake in teaching my kids that everyone is the same," he said.

Mostly he has tried to prepare his children for what he knows will be a rough career road ahead. "Blacks have to be 50 percent better, if not twice as good as whites to get the same position," he said. "So I have to guide my kids."

Mnikati's own attitudes toward whites are an ambivalent mixture of resentment, envy and, always, suspicion. There are few friendships among his coworkers, and only one white has invited him to her home.

"A lot of white people make the right noises," he said. "The question is when it comes to the crunch, when you're faced with the prospect of having a black neighbor, will you still make the same noise?"

Wellington Mnikati pulled himself up from poverty with less than a high school education. He drove himself through a series of low-level jobs, starting as a janitor in a cigarette factory and working up to senior wages clerk in a construction firm.

He left for Rank Xerox when it was clear that he never would rise to an accountant's position even though he was doing an accountant's work, because that classification was reserved for whites.

"I could only give instructions to white women in the form of suggestions," he recalls.

He managed to get his high school diploma at night and is now one course away from a bachelor's degree in business.

At Rank Xerox he is personnel manager, and he is proud of his company's record on equal employment opportunities. But he always feels the tension between being black and being a corporate manager.

"It would be easier for my white counterpart to make an economic decision to fire blacks because at the end of the day he goes home in the opposite direction, while I would go home in the same direction with the same people I just fired," he added.

As political unrest continues, Mnikati fears that the tension between the two worlds in which he lives -- the corporate world and Soweto -- will only worsen. He feels trapped between young black radicals whose cry for freedom he sympathizes with but who see him as a capitalist enemy, and a system he despises yet is increasingly identified with.

"I am an outsider in both worlds," he said. "You understand the situation and you sympathize with the kids, but at the same time you feel like a piece of meat in a sandwich."

That was one of the main reasons Mnikati had decided to sell his old house in the township of Moroka and build a new one in Diepkloof Extension, a wealthier new area a few miles closer to Johannesburg and more removed from Soweto's turbulent center.

But even the new area is not sealed off from the reality of Soweto. Most of the schools in Diepkloof have been closed much of this year due to boycotts and violence. A few blocks away from Mnikati's lot stands the burned shell of the once-grand house of a community councilman. It was destroyed by a mob that branded him a collaborator with white rule.

Down in a valley a few minutes away is a collection of squalid, all-male barracks, mounds of garbage piled against the walls, where blacks from rural areas are housed while they work on annual contracts. The men who reside there, cut off from families and friends, prowl the streets at night.

On his way home from taking his daughter to her Saturday lessons, Mnikati always buys a Johannesburg Star so he can glance at the real estate ads for whites. He and his wife Cannie often take a Sunday drive to view open house displays in newly developed white suburbs.

There, among freshly painted, two-story houses with balconies and trim yards, is where Wellington Mnikati's real dreams reside.

Other blacks go too, he said, despite the fact they cannot buy. "A lot of us just go there to drool," he said.

Sipping tea in his living room, Mnikati paused briefly to glance at his children. Then he reiterated his impatience: "We are the people feeling the pinch, so we don't have the luxury of waiting until whites see the light," he said. "All I'm asking for is to untie the one hand from behind my back."