Laissez-faire means "leave it alone." Usually it describes the economic policy of a government that stresses non-interference in business.
The phrase laissez faire comes from the French phrase laissez faire et laissez passer, "Let be and let pass." This phrase became popular in 18th Century France, where economists suggested the government stay out of business and industry. It might also be applied to situations outside economics where governmental interference in personal activities is avoided or when you take a "hands off" approach to something.