The Launch Room is the chamber in which the tributes make their final preparations for the Games, and are launched into the arena, hence the name. Each tribute is assigned their own individual Launch Room.
The Launch Rooms are in the catacombs under the arena and are accessed by traversing many underground passages after descending a ladder from the hovercraft that takes you to the arena. These passages are presumably labyrinthine in nature in order to prevent tributes from meeting each other under the arena.
Little is known about the contents of the Launch Rooms, only that they contain showers, sofas, and access to food and drink. Tributes are accompanied by their stylists, who help prepare them in the clothes provided by the Gamemakers.
Tributes are then launched from a tribute tube, a glass cylinder that contains the Launch Plate, a metal disk that ascends from the launch room into the arena. All tributes are launched at the same time, in a circle that surrounds the Cornucopia, which lies in the centre of the circle, usually inspiring a bloodbath for the items stored within.After the launch, each tribute must remain on their launch plate for 60 seconds, as a wrong step will trigger the land mines and will result in instant death; after this time period, the land mines deactivate, and the Games begin. Katniss says that a girl once dropped her tribute token, a wooden ball, and the Peacekeepers had to literally scrape her decapitated body parts off the ground.
According to the video footage of the 50th Hunger Games, the Launch Rooms and tribute tubes, like the arena, both contain hidden cameras, as the arena is first shown from the perspective of one of the tributes as they launch.
As each arena is only used once, each Launch Room is only ever used by one tribute.