For general emergency, call 112

Ambulance
tel. (+420) 155

Police
tel. (+420) 156 or 158

Fire
tel. (+420) 150

There is an emergency site that can help direct you to the appropriate network. There is even a section dedicated to expat's, "Through Expat's Eyes". There is also a municipal police site (unfortunately only in Czech), that is useful.

Safety

Prague is generally safe, but scams can be found in any major capital city. Here are some general tips to protect yourself.

All of Prague is notorious for pickpockets. You will notice multi-lingual advertising campaign warning of the danger. Be prepared and watch your surroundings. If you feel threatened, make some noise and get away from the situation. The metro station and trams N22 and 23 are some of the most notorious spots. Ask for ID from anyone who asks to take your ticket or passport. Note that professionals often work in teams and pinpoint tourists and backpacks. Also beware of small children, they are often utilized as they are not prosecuted by Czech laws. Just be careful.

There have been reports of very friendly girls around tourist areas and Wenceslas Square. A suggestive grope may actually be a talented pickpocket. Also beware their "recommendations", they may be steering you into expensive, or potentially dangerous places.

Only exchange money with official offices that post their prices. Be wary of offices that claim 0% commission. Never change money on the street.

Taxis are notorious for ripping off tourists. Avoid flagging down a taxi and try to call ahead if possible. Especially avoid flagging hotels down from ritzy hotels or restaurants. Also check the company is legitimate, the name should be on the vehicle. Lastly, make sure the meter is running and accurate.

Prague also has a problem with beggars. There are many around the main tourist areas. If you take a photo, it is expected that you should also give them some money.

Possession of drugs is a difficult thing to define in the Czech Republic. In early 2010, the term "an amount less than small" has been translated to less than 15 grams of marijuana, 5 patches of LSD, 1 g of cocaine. Please also note that most bars will expect you to go outside if you intend to smoke a joint.