TOKYO -- A masked man brandishing a knife broke into a bank recently, making off with about $17,000 in cash. Less than a half-hour later a middle-aged woman showed up at the bank, said she was the robber's wife and apologetically returned the money.

A few minutes later the bank robber himself confessed.

Here in one of the world's most crowded industrial countries, the heist made national news -- as much for having occurred as for the unusual way in which it was solved.

By the standards of the United States, or any other major industrial country for that matter, Japan is nearly crime-free. Muggings are unheard of, rape is infrequent and murders are rare. Even marijuana use is minuscule.

Police shootings are so uncommon that when the police shot and killed an apparently deranged man a few weeks ago, the chief of police gave an apologetic explanation and the newspapers pointed out that it was the first such fatal shooting by police in two years.

Fear of crime is so low here that people regularly walk around with wallets bulging with cash, women travel the subways late at night alone and old people, responding to a survey last year, said they worry more about traffic accidents and natural disasters, such as earthquakes, than they do about crime.

"Japan is an exceptional country in this respect. Forty years after World War II, crime has stayed basically at the same level," said Japanese crime expert and former police reporter Takuro Suzuki.

Last year Japanese police recorded a total of 1.6 million crimes, almost exactly the same number as occurred in 1948. By contrast, the United States had more than eight times that amount, with a population only twice as big as Japan's.

National Police Agency statistics present an even more glaring comparison: the United States has more than 10 times as many murders, 45 times as many rapes and more than 270 times as many robberies.

And while Japan solves more than 95 percent of its murders and 80 percent of its robberies, the United States solves less than 75 percent of its murders and a little more than 25 percent of its robberies.

How has Japan avoided what many experts consider the inevitable scourge of modernization? Police and other crime experts suggest several explanations.

As an island nation of basically one race, culture and language, there are fewer causes for resentment and misunderstandings. While Japan is rich, its wealth is fairly evenly distributed and the hostility between haves and have-nots in the United States and elsewhere hardly exists in Japan. In addition, while unemployment has been going up, it is still remarkably low, at about 3 percent.

The Japanese have a deeply instilled respect for the group above the individual and a strong sense of wanting to avoid shaming one's group, instincts that act as deterrents to crime.

"Looking way back in history we are the so-called agricultural people. You are the hunter people. We plant rice. Especially in the old days, you can't plant rice without cooperation," said Iso Kobayashi, deputy police chief for Tokyo's busy Shinjuku section.

Group psychology frequently helps police after a suspect is caught. "Often they feel very guilty and confess and then give the police tips on how to prevent the type of crimes they were involved in," said a Tokyo metropolitan police inspector, Tsutomu Kirino.

Experts say that many Japanese also continue to adhere to Confucian traditions of respect for authority, which today translates into respect for police and increases willingness to cooperate.

Gun control is very strict and access to handguns has been tightly regulated for 400 years. Today, only those involved in law enforcement may possess handguns. Even handgun-sized antique pistols are illegal unless the owner has a special license, which can be obtained only for guns that came to Japan before 1867. Only one factory in Japan makes handguns and its location is a police secret.

Drug laws are also very harsh.

While many areas of the United States have only begun to use the 911 emergency police number system, Japan, in contrast, has had a nationwide police emergency telephone number, 110, for almost 40 years. Police say this has helped promote crime reporting.

Finally, police and crime experts cite Japan's widespread use of small, neighborhood-oriented police stations, known in Japanese as koban.

There are 15,000 such police stations across Japan, and in rural and suburban areas a policeman and his family live in them. Crime experts and police officials acknowledge that the koban probably do more to combat crime than computerized fingerprinting and other high-technology, anticrime techniques Japan now employs.

From these stations the police make regular rounds, usually on foot or bicycle, through every neighborhood in Japan, literally knocking on the door of each house to register its occupants and inquire about neighborhood issues.

According to the National Police Agency, policemen here spend much of their time counseling citizens on everything from money matters to divorce, pursuing youthful hot-rodders, warning teen-agers to stay away from drugs and issuing neighborhood news bulletins about the good deeds (such as returning lost property) performed by neighborhood children.

The idea that policemen should be out walking the beat is so firmly entrenched here that the Japanese name for policeman is Omawarisan, Mr. Walk-Around.

Because serious crime is so low in Japan, these patrolmen spend much of their time on little things: In Tokyo's busy, upscale Ginza shopping district, a policeman on duty recently held onto an older woman's purchases while she finished her shopping.

One recent night in the police station in Tokyo's crowded Shinjuku train station, located in the heart of the entertainment district, patrolmen were busy giving directions and meeting with a neighborhood crime-prevention group that twice a week accompanies the police officers on their rounds.

Shinjuku is in many ways Tokyo's equivalent to New York's Times Square and 42nd Street area -- always busy, crowded, full of night-time carousers visiting nearby bars and sex shops. But policeman Shigenori Hoshi described a much tamer scene than one would likely find in Times Square.

While his station has responded to its share of bar-related brawls and even an occasional hoodlum-inspired shooting, the more common fare is lost packages and intoxicated office workers who need to be helped onto a train or protected from pickpockets if they pass out in the station.

Although much of this is reminiscent of small-town America in the 1950s, many Japanese worry that Japan's low crime rate, like small-town America, may soon vanish.

"Times have changed, especially in the big cities, and maybe people have started to think 'I don't want to get involved,' " said Tateshi Higuchi, assistant director of the criminal planning division for the national police. "It's happening, and it makes police investigations more difficult."