By ADAM LIPTAK

In the late summer of 1985, Kurt Parrott, a 15-year-old who loved baseball and Pac-Man, was thrown from his motorcycle in Opelika, Ala. The buckle of his helmet failed, and he died when his bare head hit the pavement. Mr. Parrott’s mother sued the Italian company that made the helmet, and an Alabama court awarded her $1 million.

The company refused to pay. And last year, when lawyers for the Parrott family tried to collect in Italy, they were blocked by the Italian Supreme Court.

The court said that a peculiarity of American law — punitive damages — was so offensive to Italian notions of justice that it would not enforce the Alabama judgment.

Most of the rest of the world views the idea of punitive damages with alarm. As the Italian court explained, private lawsuits brought by injured people should have only one goal — compensation for a loss. Allowing separate awards meant to punish the defendant, foreign courts say, is a terrible idea.

Punishments, they say, should be meted out only by the criminal justice system, with its elaborate due process protections and disinterested prosecutors. It is not fair, they add, to give plaintiffs a windfall beyond what they have lost. And the ad hoc opinions of a jury, they say, are a poor substitute for the considered judgments of government safety regulators.

Some common-law countries do allow punitive damages, though in limited circumstances and modest amounts. In the United States, by contrast, enormous punitive awards are relatively common, although they are often reduced or eliminated on appeal. Last month, for instance, the United States Supreme Court heard arguments in the Exxon Valdez case, where a jury’s initial award of $5 billion was later reduced to $2.5 billion.

Still, such awards terrify foreign courts.

“The U.S. practice of permitting a lay jury to exercise largely discretionary judgment with limited constraints in awarding punitive damages is regarded almost universally outside the U.S. with a high degree of disfavor,” said Gary Born, an American lawyer who works in London.

Foreign lawyers and judges are quick to cite particularly large American awards. Julian Lew, a barrister in London, recalled a Mississippi court’s $400 million punitive award against a Canadian company in 1995 with scorn. “It did bring America into total and utter contempt around the world,” Mr. Lew said.

Yet there are signs that the gap between the United States and the rest of the world is narrowing, as American courts and legislatures start to limit punitive awards and other countries start to experiment with them.

Punitive damages have deep roots in American and English common law, but their nature has changed here over time. “Until well into the 19th century,” Justice John Paul Stevens of the Supreme Court wrote in 2001, “punitive damages frequently operated to compensate for intangible injuries” like pain and suffering or emotional distress.

These days, driven by the structure of the American civil justice system, entrepreneurial plaintiffs’ lawyers and the populism they embrace, punitive damages are used to send messages to large corporations, to fill gaps in regulation and to reward successful plaintiffs with multiples of what they have lost. Distinctive features of the American legal system — civil juries, class actions, contingency fees and the requirement that each side bear its own lawyers’ fees — all play a role in amplifying punitive damages.

Punitive damages are so embedded in the American legal system that the rationale for them is rarely explored. One of the best explanations came from a German Supreme Court decision in 1992, which said the concept had four main purposes: to punish the offender for “uncivilized conduct,” to deter the offender and others from doing similar things, to reward the plaintiff for enforcing the law and so improve “general law and order,” and to supplement inadequate compensatory damages.

The case decided by the German court, like the one involving Kurt Parrott, was an effort to enforce a judgment from an American court against a defendant who had no assets in this country and refused to pay. Ordinarily, it is a relatively routine matter to ask a foreign court to enforce an American court judgment. Not so when punitive damages are involved, even where the conduct in question is shocking.

The German case, for instance, involved sexual abuse. In 1985, a state court in Stockton, Calif., entered a $750,000 judgment, including $400,000 in punitive damages, against Eckhard Schmitz for abusing a 13-year-old boy. Mr. Schmitz would not pay, and he fled to Germany while he was appealing a 13-year criminal sentence for engaging in sex with other teenage boys.

But the German court nonetheless said that the dangers of allowing punitive awards outweighed the benefits. The plaintiff should not get a windfall, the court said, and should not be allowed to act as a “ ‘private public prosecutor’ infringing the German state’s monopoly on punishment with its associated safeguards.”

The German court did enforce the $350,000 compensatory award. The Italian court, by contrast, refused to enforce any of the $1 million award to Kurt Parrott’s mother because the Alabama judge had not said how much of it was for compensation and how much for punishment.

But “the tide may be about to change,” John Y. Gotanda, a law professor at Villanova, wrote last year in The Columbia Journal of Transnational Law. “Traditional hostility to American awards of such damages may be dissipating.”

That is partly a consequence of changes here. American courts and legislatures are experimenting with ways to limit punitive damages, often in response to lobbying and litigation from business groups that say huge punitive awards are arbitrary, unfair and hurt the American economy.

Five states — Louisiana, Massachusetts, Nebraska, New Hampshire and Washington — ban or severely limit punitive damages. Others restrict the amounts awarded. Some states, responding to the criticism that the awards are a windfall for the plaintiffs, require that a part be turned over to the states.

The United States Supreme Court has in the last decade or so started to impose its own limits. In 1996, it ruled that a $2 million punitive award in an Alabama consumer fraud case involving a $4,000 compensatory award was excessive, given that the harm was merely economic, far exceeded the maximum punishment the state could have imposed and was disproportionate to the compensatory award.

In 2003, the court said that the ratio between punitive and compensatory awards must typically be in the single digits to be constitutional. It struck down a $145 million punitive award in an insurance fraud case where the compensatory damages had been $1 million.

At the same time, courts in a few countries around the world are expanding the availability of punitive damages.

The Tribunal Supremo in Spain, for instance, enforced a $1.3 million punitive award in a Texas trademark and unfair competition case in 2001. The Supreme Court of South Australia in 2005 indicated that it would consider enforcing American punitive awards where they involved “brazen and fraudulent conduct.”

Perhaps most notably, the Canadian Supreme Court in 2003 upheld a $50,000 punitive award in a Florida land dispute, saying it “does not violate our principles of morality.”

Justice Louis LeBel explained, with an air of resignation, why this was so, saying there was nothing in the American approach that was inherently offensive to Canadian ideas of basic fairness.

“It is simply a different policy choice,” he wrote, “and it affords U.S. plaintiffs a level of protection of which they ought not necessarily to be deprived just because the defendant’s assets are here.”

Even in Germany, which flatly rejected an American punitive award in 1992, there are signs of change, said Franco Ferrari, a law professor at the University of Verona in Italy. “The traditional compensatory regime has been permeated by punitive elements,” he said.

In cases involving a fake interview with Princess Caroline of Monaco, intellectual property and employment discrimination, he said, German courts have started to award damages that seem to be meant to punish as well as compensate.

Kurt Parrott’s mother, Judy Glebosky, learned about the Italian Supreme Court’s decision from a reporter. Her lawyers had turned the matter over to an international collection agency and had not bothered to tell her that she had lost.

The case seemed simple to her.

“I bought Kurt a helmet that was supposed to be the best,” Ms. Glebosky said. “It did not perform, and I lost Kurt.”

Questions about punitive damages seemed academic to her, if not heartless.

“A million-dollar award is really nothing,” she said. “It’s really not enough to punish any large company in this day and age, and it certainly does not bring back Kurt.”