In recent years, some decisions from the NLRB are leaning in the direction of multiple unions: https://laborblog.vorys.com/2014/07/articles/nlrb/how-many-unions

In recent years, some decisions from the NLRB are leaning in the direction of multiple unions: https://laborblog.vorys.com/2014/07/articles/nlrb/how-many-unions-can-your-workplace-support https://laborblog.vorys.com/2014/07/articles/nlrb/how-many-u... The idea is that different kinds of workers could be in different unions. A department store might have, for example, cosmetics specialists, tailors, accounting staff and so on; and these groups are distinct enough, from the NLRB's perspective, to have their own unions.