PARIS — If you're a woman living in a city, this has probably happened to you. You're by yourself on a bus or a subway. Maybe you're wearing heels and a dress, or just your boyfriend's dirty old sweater. Suddenly you notice a man is staring at you, and won't stop. Maybe he starts saying vulgar things to you. Or maybe he never says a word. Maybe you only realize there's a creep on this ride after his hands are on your body.

Sexual harassment on public transportation is a local problem — and a global plague. Fortunately, over the past few years, a growing awareness of the issue has finally led some governments and companies to act. In Tokyo, the city launched a campaign last month to combat what is known in Japanese as "chikan," the groping of girls and women in subways.

Yes, the freedom to move in peace through the city is one of your most basic rights. You need to get to work, to class, or wherever the hell you please. Here's what happens every day to women around the world, and how some cities are taking action:

JAPAN

While children are told not to talk to strangers, parents and teachers do not teach them about harassment in the subway. This means that far too often, crimes go unreported. Experts say that longstanding sexism and patriarchal dominance often provokes a feeling of guilt for the victims of sexual assault, and recent studies showed that only 5% of such crimes in Japan are reported to the police. Tokyo city officials want to change that with the new advertisement campaign in the subway to encourage women to speak up. This follows another effort in the southern Japanese city of Fukuoka, where a smartphone app was launched in February that allows students to signal zones where women were being assaulted on a map. An emergency button to directly call the police has also been set up.

MEXICO

In Mexico City where nine out of 10 women feel unsafe riding the subway, a "reserved for men" seta was designed : in the shape of a male torso and a penis, it was supposed to make men understand what some women have to go through. Although it helps raise awareness on sexual assault, it sadly doesn't denounce catcalling...

YEMEN

Some women have been resourceful in how they fight back. Imane, a young woman in Yemen, told the Middle East news site Al Monitor that she stabbed a groping man's hand with the pin that was keeping her headscarf in place. According to Egypt-born feminist writer Mona Eltahawy, Yemen also offers a perfect counter-point to the absurd argument that women are assaulted due to provocative clothing they're wearing: Yemeni women are regularly harassed, even though they are often entirely covered.

FRANCE

In Paris, Le Monde reports that the "brigade anti-frotteurs" (anti-groping brigade) patrols the metro undercover and tries to catch sex criminals. Like in Japan, women in France often do not file a complaint against these public perverts. Police in the capital have tried to educate women on the importance of speaking up as some men rip a hole in their pocket to be able to masturbate to female passengers. When arrested, these criminals can be sentenced to prison and their DNA put in a database to help identify them in case they attack someone else.

French public service poster: Miss!/You look charming/Can I get to know you?/What's your number?/Is this little skirt for me?/You're turning me on/You know you're hot?/ I'm gonna bang you/Answer me you bitch/STOP-THAT'S ENOUGH)

U.S.

Complaints against sexual harassment on the subway to the New York police department were up by 50% in 2016, according to the Wall Street Journal. Officials say that this doesn't necessarily mean that harassment is rising, but rather that more women are testifying.

INDIA

In India, where 80% of women face harassment in cities, according to Reuters, women-only taxi services have been launched to avoid any assault by drivers. Some subway cars in Delhi have also been reserved for women.

Ultimately, however, segregating the sexes is not the answer to harassment on public transportation. Women must be encouraged to denounce those who target them. Witnesses must be made aware, and be ready to help. And society at large must understand that this is not bad behavior: It's a crime.