A green room is a space in a performing venue which is set aside for performers to lounge in when they are not required on stage. It is typically set apart from the stage and the audience, so that the actors can hold conversations and play games without being heard by the audience. A green room is usually equipped with couches and chairs, reading materials, and games, and is a popular place to unwind after the show as well.

Unlike dressing rooms, another popular lounging area, the green room is not equipped for preparations to go on stage, and is designed as a purely recreational area. It also not usually established with the intent of being a peaceful and quiet space; the green room is an area for socializing. Actors who need quiet before going on stage usually find other areas of the theater in which to focus.

The origins of the term are unclear. The first usage of “green room” in reference to a backstage waiting area was in a play in 1678, The True Widow. Numerous theories have been bandied about to explain the term, but two are more likely than others. During the Shakespearean era, some actors prepared themselves in a room filled with plants and topiary, because the plants provided humidity, which was believed to be beneficial for the voice. This explanation seems less likely when one considers that not all theaters had space for plants.

The most likely origin of the term is the traditional association of the color green with actors. Many performers staged plays outdoors on the grass, or green, and some stages were draped or covered in green material. Liveried actors wore green, and the stage, was called “the green.” Since the color is associated with actors and the green room is a private place for actors to socialize, calling it the “green room” would have distinguished it from rooms with another function, like dressing rooms, and would have emphasized that the green room was for actors only.

A modern green room usually includes monitors so that actors can be ready for their appearances on stage. There is often a separate intercom so that staff can communicate with actors, and the green room often opens onto a deck or covered outdoor area so that actors can smoke. On television shows, guests and presenters often meet each other in the green room before the performance, allowing them to break the ice with each other before appearing in front of an audience. Some smaller theaters have dispensed with green rooms altogether, due to space restrictions.