This Friday marks Cinco de Mayo, a commemoration of the Mexican army's 1862 triumph over France at the Battle of Puebla during the Franco-Mexican War (1861-1867).

In the United States large celebrations are experienced with regional foods and cocktails. Ensure the evening ends with as much cheer as it started with and follow tips from Mother's Against Drunk Driving (MADD) for getting home safely.

• Be as non-confrontational as possible.
• Suggest alternate ways of getting to their destination — a cab, a sober driver, public transportation.
• Remember that the person you are talking to is impaired — talk a bit more slowly and explain things more fully than if you were speaking to a sober person.
• Explain that you don’t want them to drive because you care and you don’t want them to hurt themselves or others.
• Suggest that they sleep over.
• Enlist a friend to help you or to act as moral support — it’s more difficult to say "no" to two (or three or four) people than one.
• If possible, get the person’s keys. It is far easier to persuade the potential driver when you hold this leverage.
• If all else fails, call law enforcement. It’s better to have a friend arrested than injured or killed.

Feliz Cinco de Mayo! 

Source:

http://www.madd.org/drunk-driving/how-you-can-help/tips-how-to-prevent-someone.html