Crime

In most populated areas, visitors risk becoming the victim of crime.

This article describes advice on the risks to become a victim of crime. See Wikivoyage:Illegal activities policy for guidelines on how to write about crimes that a traveller might commit. See authority trouble and diplomacy for how to handle being accused of crimes while abroad. See history of justice and organized crime tourism for crime-related attractions.

Travellers pose a high risk for theft and other property crime, since criminals exploit their ignorance, confusion, and need to bring valuables.

Types of crime

Pickpockets often target travellers.
Common scams; scams and confidence tricks can be very elaborate. In some cases, they are legal by the letter of the law, or might deceive the victim to commit a crime themselves.
Robbery can be a traumatic experience.
Burglary and theft may take place at the hotel room, or wherever the traveller sleeps.
Molestation might happen in crowded places such as nightlife and public transportation. Prevalence and reactions to molestation can depend on cultural factors.
Physical violence may be directed against various categories of travellers; hate crime might target LGBT travellers in some regions, and people of a certain religion or ethnicity in other places. Though most victims of street violence are young men, women are at higher risk for certain crimes, from purse snatching to sexual assault.
Vandalism might damage vehicles or other property.
Corruption and bribery are government officers' misuse of power to extract money or other things of value from travellers and other civilians
Counterfeit money, tickets or other items of value
The black market includes sales of goods or services which are illegal in general (narcotics etc), or unauthorized or untaxed in the specific case (gambling, taxi services etc).

General precautions

“

At every door-way ere one enters,
one should spy round, one should pry round
for uncertain is the witting
that there be no foeman sitting,
within, before one on the floor.

”

—Hávamál

Several bits of common sense may help you stay out of trouble:

Before

Research into your destination, its general layout, and crime risks typical to the destinations.
Get information about ethnic and racial conflicts at your destination. Ethnic tension, racism and cultural clashes in general can provoke brawls, vandalism or other crime. In high-tension areas (such as war zones) or places with recent ethnic violence, locals might view strangers with suspicion; visitors can become victims just for being perceived to belong to, or fraternize with, an "enemy" ethnic group (or even a rival city).
Nationality aside, the local population's attitude to tourists can vary greatly. Isolated communities might be curious enough about visitors to be a nuisance. In other communities, the attitude to tourists can be outright hostile.
Some crimes and scams can be targeted towards a specific group of visitors; for instance, pickpockets in Europe tend to seek out visitors of East Asian origin, as they tend to have cash and electronics on hand.
Some destinations are infamous for hate crimes against homosexuals, transgender people, or any person perceived to belong to a sexual minority. See also LGBT travel.
Don't carry unnecessary amounts of cash or expensive items. If you travel to high-risk areas, leave expensive watches and jewelry back home, and only bring electronic equipment which you can afford to lose.
Learn the routine for blocking your credit cards in case you would lose them.
Keep family, friends, and travelling companions informed of your plans.

On site

Follow the news to stay informed about current events at your destination.
In high-risk areas, try not to expose yourself as a visitor. Lose the string of cameras around your neck, dress and act as the locals do, without typical "tourist" accessories, such as souvenir shirts, big cameras, maps or backpacks. Not only does this reduce crime risk; it also makes fraternization with locals easier.
A car with foreign license plates, rental car logos, loads of baggage, or other signs that it is not driven by locals, might attract criminals. If you can, keep luggage hidden
A laptop with foreign-language stickers can mark you as a foreign tourist. In addition, stickers related to software development or your company can make you a target for industrial espionage. Be weary of evil maid attacks, where somebody tampers with your device, such as installing a key logger. Locked devices are usually not immune.
Alcohol and other drugs affect your judgment, and should be indulged in only among people you have good reason to trust. Never consume a drink that you have left unattended.

Warning signs

Some high-risk places are low-income countries, low-income neighbourhoods, touristed areas, transportation hubs (rail stations, airports, etc) and nightlife districts. Places open to the public (landside area of airports, outside public transportation gates, the bar section of a restaurant, etc) tend to be less safe than places with restricted access.
Avoid anyone begging, particularly if they're using children to beg on their behalf.
Avoid people, especially groups of young men, who loiter around in a public place.
Being in any situation where you are among a group of strangers who all know one another but not you gives them a great deal of power over you.
Be wary of attractive-looking strangers trying to raise your sexual emotions; including strippers or prostitutes.
Crowded and/or noisy events such as festivals, markets, sport events and street performances are hotspots for pickpocketing and brawls. Some performances are set up as part of a criminal scheme.
Nightfall; though city streets are usually well-lit at night, the absence of honest witnesses and security personnel increases the risk of crime. Office districts might get deserted as early as 5 PM.
Deserted in the daytime; If you enter an area of town that's completely deserted when nearby neighborhoods are bustling with activity, it could be a sign that locals don't feel it's a safe area. A lack of witnesses can make this just as dangerous as a street at night.

Reaction

You are not required to be polite or friendly to anyone who refuses to leave you alone when you request it.
Nor are you required to answer getting-to-know-you questions from random people. These may just be friendly locals, but they might also be scammers looking for information useful to them.
Use local language to shout out words such as "help!" or "thief!"