STANBUL — In his sweater and corduroy pants, Halil Berktay looked every inch the history professor that he is. But his words made him sound like a fatigue-wearing guerrilla.

"We are a threat to mediocrity and underfunding and the sclerosis of the state education system," he said as he paced his office. "It is a challenge to change and evolve and keep up."

Dr. Berktay is an outspoken insurgent in a generally quiet revolution to reform and modernize higher education in Turkey. He enlisted when he left Bosporus University, one of the country's best public institutions, and signed on at Sabanci University, the newest of Turkey's private universities.

Sabanci is trying to create a new model for a Turkish university. Devised by a team of international academics, the school emphasizes interaction between students and teachers and free exchanges between academic disciplines. It is recruiting top-notch professors from abroad, mostly from the United States, by paying them well and offering plenty of money for research.

Sabanci is not alone; 15 new private universities have opened in the last five years. But Sabanci's establishment two years ago by one of Turkey's wealthiest and most influential families and its sleek $200 million campus raised the bar in the effort to remake education.

"We want to do our business so well that other universities will copy us," said Tosun Terzioglu, the university's president. "If we can do that, it will transform Turkish society in 10 years."

Turkey is grappling with a problem that confronts many developing countries: how to modernize huge centralized university systems to respond to the challenges of a fast- changing new era.

The revolution here is not without opposition. The bureaucracy in Ankara has blocked changes, and Islamic-oriented politicians tried to stop construction of one school.

Turkey had the beginnings of a private university system, but private universities were outlawed in the 1970's during a period when they faced huge financial problems. The state took over all higher education. In the early 1980's, new rules were written under which private universities are permitted if they are operated by a nonprofit foundation and supervised by the state Council of Higher Education.

But administrators at some public universities see the upstarts, with their big budgets and the flexibility to shift spending in response to the education market, as a threat.

"The private universities are trying to lure away our best professors by offering three or four times as much money, and it is very hard for us to attract young professors," said Sabih Tansal, president of Bosporus University in Istanbul.

In Turkey, about 1.4 million high school seniors take the university entrance examination each June. The score is the sole factor in determining not only who gets into a university, but also which universities students will attend and, through a complex computer matchup, which subject each will study.

Last June 300,000 students scored well enough to qualify for a four-year university, but there were slots for only 167,000, including those at the private universities.

Space has not kept pace with the increase in Turkish men and women seeking higher education. And resources are spread thin among the 53 state universities, which depend on government money because they do not charge tuition. Spending per student has declined steadily, classrooms are overcrowded, new equipment is lacking and salaries are very low. (Tenured professors are paid $12,600 a year and new professors with a doctorate get $7,440.)

Some public universities have maintained good reputations. But even the best have deep financial troubles, and critics contend that most public universities also suffer from rigid bureaucracy.

The impact of private universities is small so far. Turkey's 19 private universities have an undergraduate enrollment of about 20,000, about 3 percent of the 660,000 students at four-year schools.

Tuition at the private universities ranges from a few thousand dollars a year to $10,000. But university administrators said the need to pay tuition is not an insurmountable problem, pointing out that 40,000 Turkish students study in the United States, where costs are much higher.

The first private school under the new rules was Bilkent University, which opened in 1986 in Ankara. It has grown to 11,000 students and established an excellent reputation.

The second, Koc University, opened in 1993 on a campus north of Istanbul overlooking the Black Sea. It was financed by the Koc family, which, like the Sabancis, runs a powerful business empire, and the emphasis is on business school. Like its American counterparts, Koc wanted to choose students through interviews and a test similar to the College Boards.

But shortly before the school opened, officials got a letter informing them that they would have to accept students by entrance exam score alone, like everyone else.

Seha M. Tinic, a Turk teaching at the graduate school at the University of Texas in Austin, had been picked to run Koc. When Mr. Tinic heard about the change, he said, he advised the trustees not to start the university. But the board accepted the government's demand and Mr. Tinic came anyway.

Then the Istanbul municipal government, run by the Islamic-oriented Virtue Party, went to court to block construction of the school. The government contended that its construction would destroy too much forest, but Koc officials contended that the objections were really over the school's Western style of education. The case was eventually settled in Koc's favor.

Measuring success is difficult for a young school, but graduates average 2.5 job offers each and 10 percent have gone on to graduate schools in the United States.

Most classes at the top Turkish universities are in English, the language of many academic materials and journals and of international business, and the United States is the standard for most of the private universities.

Not all private schools are as wealthy as Koc and Sabanci. Istanbul Bilgi University is a five-year-old school making its mark as an urban university. Freshman attend classes in a former Toyota dealership, and the main campus is in a working- class neighborhood. The school has developed innovative programs like an M.B.A. via the Internet and a jazz department.

"State universities expanded by taking in more students, but often that resulted in an impersonal atmosphere," said Ilter Turan, Bilgi's president. "We offer an alternative to the urban middle class."

Ambitions are high at Sabanci University, whose campus sits on a dreary hillside about 45 minutes from the city center. The curriculum was conceived over two years in meetings with more than 50 international academics, with a goal of structuring the university of the future.

Equipment and classrooms are state of the art. Entering freshmen are given IBM laptops, and 8,000 Internet connections are scattered across the campus, from classrooms to grassy outdoor areas. "I'm interested in genetics and you can't find labs of this quality in the state schools," said Tolga Sutlu, 19, as he worked on his laptop in the library.

The school, in its second academic year, has 750 students, with plans for a maximum of 3,000. "Not very often does an academic have an opportunity to start a university from scratch," said Mr. Terzioglu, the president. "The Sabanci family lets me lose $20 million a year."