The formula was named after Supreme Court Justice Ivan Rand, after a Ford Motor strike in Windsor in the fall of 1945 was resolved by court arbitration. The decision made paying union dues compulsory for all workers protected by a union contract. The Rand formula has become standard procedure for collective agreements across Canada. It also ensures financial resources for unions and penalties for violating the agreement. The Rand Formula protects both workers and employers while encouraging collective bargaining. (reposted from The Dispatch)
For more information please see this article in the Canadian Encyclopedia.