s they have tried to diversify their campuses over the last three decades by giving special consideration to blacks and Hispanics, selective universities have struggled to decide whether Asian-Americans fit the definition of "underrepresented" minorities.

Part of the problem is in the very way affirmative action works, some admissions officers say. Colleges often bundle Asian students from various ethnic or racial subgroups — Japanese, Korean, Filipino, Pakistani — into one category, they note, missing the substantial differences in upbringing and education between, say, a first-generation Vietnamese student and a fourth-generation Japanese-American.

Nor do many affirmative action policies distinguish between an applicant from the black middle class, who might have been able to afford SAT tutoring, and a Chinese applicant from a low-performing urban public school.

Ed Hu, who was an admissions officer at Brown University from 1989 to 1994 and was one of the first Chinese-American admissions officers in the Ivy League, said that when he began working at Brown, "there was a lot of stereotyping of Asians" among the staff.

"Admissions people felt that all Asians were the same," he said, "that they were all pre-med or engineers, and that they all played the piano or the violin."

For example, he said, many of his colleagues did not know that Filipinos are among the largest subgroups of Asians in the United States, at least by population, yet among the poorest and least educated.

"They were natural candidates for affirmative action," said Mr. Hu, now a dean at Harvard-Westlake, a private high school in Los Angeles.

Not only weren't such students given any special advantage in the admissions process, Mr. Hu said, they were often judged against an even harsher standard than white applicants.

When Brown assembled the class of 1987, for example, it admitted 20 percent of all applicants, but only 14 percent of those who identified themselves as Asian. A committee appointed by the Brown trustees ultimately concluded that "Asian-American applicants have been treated unfairly," and the admission rate of Asians has subsequently pulled relatively even with those of the class as a whole.

The solution, Mr. Hu suggested, rests with admissions officers' being more open to the notion that Asian-American applicants might face disadvantages, and have valuable contributions to make to a campus.

At Cornell, for example, which does not formally consider Asian-Americans to be underrepresented, Ken Gabard, an admissions officer with 14 years of experience, said he had reached out to immigrants from the Philippines, Laos and Vietnam. In some instances, he said, he has not been daunted if such applicants are less accomplished academically than other Asian-Americans with more advantages.

While Cornell does not disclose its admission rates by ethnicity or race, the undergraduate student body is 16 percent Asian, 5 percent black and 5 percent Hispanic.

"It is always a question of how far you can define distinct groups as meriting special attention," Mr. Gabard said. "We know that it's an imperfect system."