How To Avoid Pickpockets While Traveling
Good article on HuffPo by Lena Katz, interviewing Bob Arno, a criminologist. An excerpt:

Among women who carry a purse or handbag, which ones are safest? How do you position the strap? What's the worst mistake you see in how they hold and look after the bag?

Bob Arno: The worst, and the most common mistake, is to hang your handbag on back of the chair, or to tuck the bag behind you on the seat. You think you have physical contact with the bag, but fifteen minutes into the meal you forget! I've seen surveillance videos in which a gang of three thieves in a well-established luxury hotel restaurant position themselves strategically around a targeted breakfast table, talking to each other on their cell phones. They wait for the perfect moment when the owner of the bag -- the victim -- leans forward. At that moment, the controller of the gang gives a small hand signal to the other two to execute their independent moves so that everything is coordinated. One accomplice creates a small diversion in front of the table, and the other observes the restaurant staff, to be sure nobody pays attention to the incident. The thief unrolls a soft jacket from his fanny-pack and drapes it over his arm, allowing the fabric to come down over the victim's handbag. He scoops up the bag under the cover of the nylon jacket. They then immediately leave the restaurant. Coffee shops (such as Starbucks and their competitors) are extremely popular venues for thieves who practice bag stealing.

Conclusion: You must have your purse in front of you and keep physical contact when traveling. If it is a purse with long strap, wear it in front of your body when you are in a vulnerable location or environment.

What's the safest place for a man to carry his wallet?

Men should carry their wallets in their tightest pocket. Still, that's not always safe enough. For added security, men might try one of four kinds of under-clothes pouches which are comfortable and functional for easy access, but which make it almost impossible for thieves to steal from.

1. A pouch that hangs from a string around your neck and is worn under your shirt.

2. A pouch that hangs from your belt by a loop and is worn inside your pants.

3. Ankle-holsters in various designs and levels of sophistication.

4. Underclothing with built-in pockets for valuables. One new product is called Stashitware. Another line is made by Clever Travel Companion.

When I'm traveling someplace like Paris, where there are pickpockets on the Métro and some other places (places I try to avoid going, like the hideous 20th arrondissement), I carry a zipped change purse with only one credit card, my ATM card, and my health insurance card, then I put it in a crinkly plastic bag. This way, should somebody get into my purse, it feels like something I bought at the drugstore, not a wallet.