A "right to work" state legally prohibits forced union participation, according to the National Right to Work Legal Defense Foundation. Workers in these states independently decide whether to join or financially support their professions' unions.
According to Wikipedia, "right to work" laws in these states limit the power of unions to collectively bargain with employers regarding pay, working conditions and job security. The National Right to Work Committee reports that as of 2012, "right to work" legislation was in effect in 24 states. Approximately 12 percent of the American workforce belongs to a union, according to CNN. The majority of these employees are teachers, government workers, and safety service officers.