Greater Union Organisation Pty Ltd, trading as Event Cinemas, Greater Union, GU Film House, Moonlight Cinema and Birch Carroll & Coyle, is the largest movie exhibitor in Australia and New Zealand, with over 140 cinema complexes currently operating worldwide.

A multiplex is a movie theater complex with multiple screens or auditoriums within a single complex. They are usually housed in a specially designed building. Sometimes, an existing venue undergoes a renovation where the existing auditoriums are split into smaller ones, or more auditoriums are added in an extension or expansion of the building. The largest of these complexes can sit thousands of people and are sometimes referred to as a megaplex.