A bouncer (also known as a doorman, door supervisor or cooler) is a type of security guard, employed at venues such as bars, nightclubs, ranches or concerts to provide security, check legal age, to refuse entry for intoxication, aggressive behavior or non-compliance with statutory or establishment rules. Bouncers are often required where crowd size, clientele or alcohol consumption may make arguments or fights a possibility, or where the threat or presence of criminal gang activity is high. In the United States, civil liability and court costs related to the use of force by bouncers are "the highest preventable loss found within the [bar] industry", as many United States bouncers are often taken to court and other countries have similar problems of excessive force. In many countries, federal or state governments have taken steps to professionalise the industry by requiring bouncers to have training, licensing, and a criminal records background check.