The Saskatchewan Federation of Labour applied to appeal before the country's top court after losing lower court battles over the province's essential services law.
The province argues the legislation, introduced five years ago, helps protect public safety in the event of a strike.
The Saskatchewan Federation of Labour and numerous other unions say it infringes upon their rights and freedoms.
One issue the top court may have to deal with is whether the right to bargain collectively is guaranteed under the Charter of Rights and Freedoms.
With leave to appeal granted, unions and the provincial government will square off before a panel of Supreme Court judges. A court date hasn't been set yet.