Since the 1960s, data on race and ethnicity have been used extensively in civil rights monitoring and enforcement, covering areas such as employment, voting rights, housing and mortgage lending, health care services, and educational opportunities. In the 1970s, the federal government standardized racial and ethnic categories in order to streamline civil rights monitoring. Henceforth, Americans would have to identify themselves as American Indian or Alaskan Native, Asian or Pacific Islander, black or white. In the one adjoining category on ethnicity, they could also choose to select whether they were of Hispanic or non-Hispanic origin.

But the logic and strength of the mutually exclusive racial categories were not destined to survive long in a diversifying nation. In the early 1990s, these standard classifications came under fire from a growing number of Americans who believed that the bare-bones options on the census questionnaire did not reflect the new demographic reality wrought by two decades of high immigration and increasing intermarriage rates.

On the 1990 census, a mixed-race American was forced to either identify himself with one ancestry or put an X by the ignoble and anonymous "other" category. As a result, advocacy groups for racially mixed Americans called for a "multiracial" category on the 2000 census, an idea uniformly opposed by traditional civil rights organizations that feared the new classification would diminish their constituencies as well as complicate the task of monitoring discrimination.

Caught in a political tug-of-war, the Clinton administration stumbled on a compromise in the fall of 1997. The Office of Management and Budget, which incidentally was headed at the time by Franklin Raines, an African-American with a white wife and mixed children, directed that federal forms, including the 2000 census questionnaire, must now tell respondents to "select one or more" racial categories to identify themselves. By choosing multiple categories, respondents could indicate a multiracial identity.

At the time, few could have predicted that this small, politically expedient yet significant change in the questionnaire's fine print would make much of a difference in this country's stagnant racial dialogue. But on the eve of the 2000 census, demographers, statisticians, and bureaucrats around the country are still not sure how they will process and present the data that is due on the president's desk by the end of the year.

While it is clear that the new multiple race option will give us a more accurate and complex view of America's racial landscape, it is also certain to create a great deal of confusion -- and perhaps conflict -- for years to come. The NAACP as well as the Asian American Legal Defense and Education Fund are urging any of their constituents who may be part white to identify themselves as simply black or Asian on the census. Other civil rights organizations are already pressuring the government to "reassign" multiracial Americans back into the traditional racial categories, to resist dilution of any individual non-white racial group.

Although the census has never been able to formally count the multiracial, surveys and estimates do show that the number of racially mixed Americans has skyrocketed over the past quarter century. In 1970, there were an estimated 321,000 interracial unions in the United States. By 1990 that number had increased to 1.5 million. Surveys also indicate that the number of children in interracial families grew from less than one-half million in 1970 to roughly 2 million 20 years later. And these numbers don't include intermarriages involving Latinos, because Hispanic is an ethnic and not a racial category.

If Hispanics are taken into account, an estimated 7 percent of contemporary Americans could be considered multiracial/multiethnic. And a recent analysis of birth records by the Public Policy Institute of California indicated that 15 percent of all births in the Golden State are multiracial or multiethnic.

In the nation's most demographically diverse state, 53 percent of multiethnic births are to Latino/white couples. At 15 percent, Asian-white children are the second most common combination, followed by black-white (9 percent), Hispanic-black (7 percent), and Hispanic-Asian (6 percent) children.

While categories and classifications have evolved over time, the census has been collecting some sort of data on race and ethnicity ever since it was first undertaken in 1790. America's ever-changing ethnic composition and shifting political moods long have been reflected in the very questions the census poses. In 1850, a growing national awareness of immigration led census takers to ask respondents' place of birth as well as that of their parents.

Forty years later, a heightened interest in miscegenation spurred census officials to track the mixed ancestry of the people we today label as African-Americans. A person was considered black only if he had three-quarters or more black blood, mulatto if he was three-eighths to three-fifths black, and "quadroon" or "octaroon" if he claimed one-quarter or one-eighth African ancestry.

Over the decades, there have been many other changes in the terms we use to identify and classify ethnic groups. Asian Indians, for example, were counted as Hindus in censuses from 1920 to 1940, as white from 1950 to 1970, and as Asians or Pacific Islanders in 1980 and 1990.

But if the new census will more accurately reflect the nation's reality, no one is clear on how to read the results. "It will be a statistical mess," says Bill Frey, a demographer at the Milken Institute in Santa Monica, Calif. "What we do know is that it's going to use up a lot of RAM."

In this year's census, the racial categories will remain essentially the same as in 1990, with a few exceptions. Black, white and American Indian or Alaskan Native and "other" will all remain unchanged. But the old category of "Asian or Pacific Islander" will be split into one classification for Asians and another for native Hawaiians and Pacific Islanders. Hispanic will continue to be a separate ethnic category.

Although there are only six major categories to select, it is the 63 possible combinations of them that could give statisticians headaches. And that's not taking into account whether those possible combinations are Hispanic or non-Hispanic. That brings the number of potential racial/ethnic mixtures to a grand total of 126.

"I can't see having to make 63 charts," says Jeffrey Beckerman, the head of statistics for the Los Angeles City Planning Department. "But I suppose that somebody might." Local officials throughout the country are still awaiting word on how the Census Bureau will release the final data. But as of early February census officials in Maryland still haven't finalized their plans. "We're still not sure how we're going to show all the information," says Arthur Cresce, a bureau demographer. "We're still working through how to do it."

"We're going to have get over the idea that everything adds up to 100 percent," says Linda Meggers, a demographer for the Georgia Legislature. Racial figures in the United States will soon resemble religious data in Japan, where 186 million people are counted as members of various sects when there are only 121 million souls in the country. In Japan, it is common for people to label themselves as adherents to more than one faith.

We do know that the bureau will release the data in a variety of formats. It will be obliged to present the entire range of combinations, but then there will also be the more abbreviated categories. The most common tables will probably be those showing the six major groupings plus one additional category in which all multiracial Americans are lumped together.

It may also choose to highlight the four major racial combinations, which in all likelihood will be white-black, white-American Indian, white-Asian, and black-American Indian. There will also probably be tables presenting "single-race" Americans alongside constituent combinations, i.e, a black alone category alongside a category for black combinations.

But despite the obvious complications in presenting the data, the real problems will come in the myriad ways people and public agencies will choose to use the numbers. And that's where the fighting begins.

For instance, it is easy to imagine advocacy groups suing over the number of members of a particular racial group. For example, a pan-Asian organization may choose to combine "single-race" Asians with Asian combinations to create a super Asian category. It is conceivable that a competing activist group, say on behalf of mixed-race Asians, could argue to have the categories tallied differently.

In fact, civil rights groups are already pressuring the federal government to develop a method of "reassigning" multiracial Americans into the traditional racial categories in data that serves civil rights purposes.

The government has discussed various ways this could work, but the final plan of action is still unclear. One option is to automatically assign people who check white and another race to the nonwhite category. Another is to have people who are a mix of two non-white groups assigned to the smaller -- and theoretically more vulnerable -- category.

Much like their contrary stance in the debate over the self-standing multiracial category, this posturing puts traditional civil rights groups in the odd position of upholding the old, zero-sum racial scheme. Indeed, some black groups, such as the NAACP and the Black Leadership Forum, a national coalition of the leaders of major civil rights organizations, are encouraging people to check just one box this year. The nuances and complexities of the multiracial future may be too threatening to the stark civil-rights era perspective forged in the segregationist past.

"I'm sure everything will end up in court," says Mary C. Waters, a sociologist at Harvard University. "Whenever you have something where resources are involved, you can imagine people arguing about it." Civil rights groups, such as the NAACP, fear that if enough African-Americans choose the multiracial over the single-racial option, they could weaken majority-minority voting districts set up in accord with the Voting Rights Act.

While recent lawsuits and legislation have reduced the role of race and ethnicity in public policy, there are still plenty of race-conscious statutes on the books. Federal policy under legislation like the VRA, the Civil Rights Act of 1964 and aid to bilingual education is based on the percentage of a certain racial group in a given place. Also, lawyers in employment discrimination suits will sometimes try to prove that a firm is biased by comparing the number of blacks in particular jobs with the percentage in the local population. Any such lawsuits could be affected if a large number of African-Americans identify themselves as multiracial.

The counting of multiracial Americans could also affect the data many counties use to monitor the racial makeup of jury pools, as well as complicate the tallying of hate-crime statistics.

Curiously, it's the keepers of health and vital statistics in states like California who may have the hardest time adapting to our increasingly multiracial reality. "I've applied to get a bunch more staff [to process the data]," says Jane McKendry, who heads the Center for Health Statistics for the California Department of Health Service. "But I don't know if I'll get them."

She admits that the department still does not know how it will classify data on mixed-race people. For instance, they have not decided what to do with an infant mortality case involving a self-described "white-black" woman -- whether it should be added to white or black infant mortality rates. "Race means a lot of things in health," says McKendry. Black infant mortality is twice as high as white in many cities, for a complicated tangle of medical, economic, cultural and perhaps biological reasons, and race-targeted strategies have brought down the mortality rate in black sections of Oakland, Calif., Baltimore and Savannah, Ga. Such strategies could be harder to pursue without an accurate count of the black population.

McKendry fears that data on multiracial Americans could get lost in a useless "mishmash" category, and that it will be hard to draw comparisons between pre- and post-2000 data. But she also speculates whether all this confusion could one day cause health professionals to wash their hands of race and concentrate solely on access to care for all Americans -- which wouldn't be a bad thing.

But, truth be told, most demographers do not expect many Americans to avail themselves of the new multiple race option, at least not this first year. In 1998, the Census Bureau ran a dress rehearsal in three sites around the country and the overwhelming majority of respondents ticked off one of the standard categories. In Columbia, S.C., only .08 percent of respondents selected more than one racial category. In Menominee County, Wis., only 1.2 percent of respondents did. But in Sacramento, Calif., 5.4 percent of respondents selected more than one race on the questionnaire.

The dress rehearsal indicates that intermarriage is a largely regional phenomenon. "There are going to be a lot of empty [bubbles] in North Dakota," says Frey, whose research has shown that the much ballyhooed ethnic diversification of America will mostly occur in the 10 states -- California, Texas, Florida, New York, New Jersey, Illinois, New Mexico, Nevada, Arizona and Hawaii -- that have become gateways to contemporary immigration.

The confusion about the census seems fitting, because it matches our racial reality much more than four neat little categories. It will also provide a welcome opportunity to reconsider the way we look at race in America. For starters, the multiple-race option undermines the logic of the so-called one-drop rule, the notion that any person with any amount of African-ancestry must be considered black.

While no one is naive enough to think that official recognition of multiracialism means that Americans will suddenly stop seeing race as a question of either/or, this still amounts to a significant first step. For instance, although the vast majority of African-Americans share some white ancestry, it is doubtful that many black Americans will label themselves as multiracial on the 2000 census. But if race is a social construct -- as social scientists love to remind us -- then it can also be deconstructed. The loosening of strict, mutually exclusive categories begins to allow for a more fluid conception of race.

After the 2000 census, the danger will be the tendency to "reassign" multiracial Americans to the old categories, or create new racial labels to "make sense" of our diversity. The more Americans identify themselves as multiracial, the less the strict categories of race will make sense in the end. But that won't keep people from trying to parse America up into four or five familiar pieces.

In 1998, for instance, the number of applicants to the University of California who flat-out declined to state their racial/ethnic backgrounds jumped a phenomenal 190 percent in one year. But university admissions officers dug into the students' SAT records to try to deduce their ethnic backgrounds without their consent.

Over the next few years and perhaps decades, there will be a heightened battle between the old and new ways of seeing race. A victory for multiracialism may not portend a new era in which all Americans are joined in a raucous chorus of "We are the World," but it would free us to concentrate on what is rapidly becoming this nation's primary demographic divide: class.

"The government really shapes whole issues of identity," says Harvard sociologist Mary C. Waters. "Over time, people will begin to answer [the race question] in more complex ways." Before the changes in this year's census, the federal government had essentially refused to properly acknowledge mixed-race Americans, the living and breathing solutions to racial tensions. The establishment of the multiple-race option was a clear recognition of a significant demographic trend.

Does all this mean that America is beginning to shed the remnants of a segregated and sordid racial past? Not necessarily. But at least now we can begin to visualize the melting pot we Americans have claimed to desire for so long.