A union organizer (or union organiser) is a type of trade union official. In most unions, the organizer's role is to hire groups of workers under the organizing model. In other unions, the organizer's role is largely that of servicing members and enforcing work rules, similar to the role of a shop steward. In some unions, organizers may also take on industrial/legal roles such as making representations before Fair Work Australia, tribunals, or courts.
In North America, a union organizer is a union representative who "organizes" or unionizes non-union companies or work sites. Organizers are mainly there to help non-union workers in forming groups of locals, usually by leading them in their efforts.
A union organizer is either elected or appointed. Most unions appoint rather than elect their organizers.