nti-Semitism is the Western world's oldest and most persistent species of hatred. There are larger and more widespread minority groups than Jews — at 13 million, they comprise about 0.2 percent of the world's population — but the Holocaust made clear how virulent hatred of them has been. To the extent that anti-Semitism persists, we have yet to fulfill the promise of "Never Again" to those who were martyred.

President Bush has asked me to head the United States delegation to a conference on combating anti-Semitism, held by the Organization for Security and Cooperation in Europe, which begins tomorrow in Vienna. The meeting is a direct response to the worldwide surge in anti-Semitic violence. Last spring, physical attacks against Jews in France were occurring at a rate of 8 to 12 a day, with 14 arson attacks on synagogues in a two-week period. In Russia, signs reading "Death to Jews" were placed along highways and rigged to explode if anyone sought to remove them.

The conference represents a critical first step for Europeans, who have too frequently dismissed anti-Semitic violence as routine assaults and vandalism. Anti-Semitism is anything but routine. When people attack Jews, vandalize their graves, characterize them in inhumane ways, and make salacious statements in parliaments or the press, they are attacking the defining values of our societies and our international institutions.

The values of tolerance and respect must be backed by more than good intentions and declarations of virtue. The attacks of Sept. 11, 2001, made clear that our principles are the true bulwarks of our security and safety. That is why, immediately after those assaults, I made it clear that the city would not tolerate the blaming of groups for the terrorists' actions: "Nobody should attack anybody else. That's what we're dealing with right now. We are dealing with insanity, with sick hatred."

I wanted to create a link between the prejudices that drove the perpetrators and any subsequent crimes directed at people because of their ethnicity or presumed beliefs.

Just as important as talking about hate crimes, New York City was acting to monitor and prevent them. The police department added a category to the CompStat crime-tracking system that accounted for bias directed at Arab-Americans. Every day the police commissioner, Bernard Kerik, would brief me on when and where such incidents were occurring and what the police were doing to combat them.

My country has struggled with its own history of prejudice and intolerance, with racism being particularly pernicious. The United States has taken several concrete steps to address these failings. Europe must now take the same approach. Tomorrow I will recommend that all 55 members of the O.S.C.E. adopt three important measures against hate crime.

First, they should agree to track hate crimes and recognize them as distinct from other acts of murder, assault or vandalism. The best way to predict and prevent crime is to assess the forces behind it accurately. For example, if several synagogues are vandalized in a short period, it is not only ineffective but intellectually dishonest to post additional police officers near all houses of worship, as if to pretend that one's nation does not have a special problem with anti-Semitism.

There is precedent for collecting such data nationally. The Hate Crimes Statistics Act, passed by Congress in 1990, requires the federal government to acquire data on crimes that "manifest prejudice based on race, religion, sexual orientation, or ethnicity." This information is an invaluable tool to police officials. It also holds them, and our elected officials, accountable for increases in hate crimes within their jurisdictions.

Second, just as important as collecting this information is making sure that it is not allowed to languish in some desk drawer. There must be analysis of and reaction to crime data on a regular basis. Critical to the success of New York City's CompStat program were weekly accountability meetings in which police officials would plan officer deployments, share successful strategies, praise good work and constructively criticize areas found to have fallen short of established goals.

Likewise, the Organization for Security and Cooperation in Europe should establish its own meetings, at least annually, at which members can compare their results to stated goals and develop effective strategies for enforcement and education. It is promising that in October, the member states will meet again in Warsaw to review their progress on the recommendations that will come from this week's meeting. Such "accountability sessions" should become a permanent part of the organization's meetings.

Last, the Europeans should pass hate crimes legislation to stiffen penalties for offenses in recognition of the special threat they represent to a society's stability. Yes, some will argue that hate crimes need not be punished more harshly than similar crimes committed for different reasons. But the fact is that extra penalties are used throughout civilized legal systems — in Europe as well as America — as a way to distinguish acts that are particularly heinous. One of the functions of the law is to teach, to draw lines between what's permissible and what's forbidden. Recognizing the special threat that hate crimes pose to a democracy sends a powerful message that these acts will not be tolerated.

These specific measures will be effective, of course, only if the O.S.C.E. countries make broader efforts to address the roots of anti-Semitism. Making sure their citizens have an honest understanding of the Holocaust is vital, as revisionist viewpoints put us at risk of a repetition of race-based genocide. Schools must look at how they educate children regarding tolerance and fairness. Universities, public officials, advertisers and the news media should publicize the tremendous contributions that Jews have made to European societies through the years.

Finally, Europe must address the climate that has allowed anti-Semitism to return with such force. Hate flourishes when excuses for the conduct are accepted, or justified by vague connections to international politics. If a synagogue is torched, the response must not be, "The act is wrong, but we can understand the reasons the arsonist feels he must resort to such extreme measures." The perpetrators must not be allowed to advance their so-called cause through violence.

Despite the alarming rise in anti-Semitic violence throughout Europe, there are strong Jewish communities all over the continent. European governments are working to regenerate the communities that played an integral role in the fabric of nations for hundreds of years. Seventy years after the Holocaust, more Jews are settling in Germany than in any other country (including Israel), increasing that country's Jewish population from 33,000 in 1990 to about 200,000 today.

I am thankful that I grew up in Brooklyn, where every conceivable ethnicity can be experienced within a few square miles. In New York, and in the United States in general, we pray with many voices — in churches, in synagogues, and in mosques — and we see that diversity of faith as one of our most important assets. All faiths suffered on Sept. 11, but they also all were strengthened. Tomorrow's meeting can help to safeguard that legacy.

Rudolph W. Giuliani was mayor of New York City from 1994 to 2001.