The game is a top-down 2D construction and management simulation where the player takes control of building and running a prison. The player is responsible for managing various aspects of their prison including building cells and facilities, planning and connecting utilities, hiring and assigning staff, including a warden, guards, workers, and more. The player needs to recruit staff to unlock more aspects of the game. The player is also responsible for the finance, and keeping their inmates content. The player's role is of both architect and governor with sandbox micromanagement themes such as choosing where to put lights, drains and how they connect together. The player is also able to add workshops to the prison as well as reform programs that reduce the specific prisoner's repeat-offender rate. The player tells the prisoners what to do indirectly by setting their schedule. The game takes inspiration from Theme Hospital, Dungeon Keeper and Dwarf Fortress.
The game was first made available on September 25, 2012 as an Alpha version. The game was then crowdfunded with pre-orders, making over US$ 270,000 in two weeks with close to 8,000 sales. Developer's co-founder Mark Morris explains that independent crowd-funding has allowed them to have no time limit on the Alpha version, as well as no fees associated with crowd-funding platforms. As of December 2013, the developers have raised over $9M. Since February the game has received 28 major updates, with the latest on January 30th, 2015.
On January 30, 2015, Introversion announced that the alpha version of the game had sold 1,066,233 copies. Introversion Software also announced that a mobile version of the game is in development and the PC version of the game will launch proper in 2015.