A confessional is a small, enclosed booth used for the Sacrament of Penance, often called confession, or Reconciliation. It is the usual venue for the sacrament in the Roman Catholic Church, but similar structures are also used in Anglican churches of an Anglo-Catholic orientation. In the Catholic Church, confessions are only to be heard in a confessional or oratory, except for a just reason (1983 Code of Canon Law, Canon 964.3).
The priest and penitent are in separate compartments and speak to each other through a grid or lattice. A crucifix is sometimes hung over the grille. The priest will usually sit in the middle and the penitents will enter the compartments to either side of him. The priest can close off the other compartment by a sliding screen so that only one person will be confessing at a time. Kneelers are provided in the compartments on each side of the priest, sometimes a prie-dieu style kneeler, or sometimes a diagonal kneeler built into the walls of the confessional. Confessions and conversations are usually whispered. Sometimes a confessional will be built into the church walls and have separate doors for each compartment; other confessionals can be free-standing structures where curtains are used to conceal penitents (and even the priest in some confessionals) from the rest of the church.
After Vatican II, the Sacrament of Penance was revised so that it more clearly expresses both the nature and effect of the sacrament (Sacrosanctum Concilium, 72). To facilitate this, face-to-face confession has been allowed. To accommodate this new form of the sacrament, many confessionals now comprise just one room. There is a screen and a kneeler to kneel on so the penitent can confess anonymously, but there is also a chair that the penitent may sit on and face the priest. In some confessionals, there may also be a chair behind the kneeler so that penitents who, due to old age or medical conditions, cannot kneel, can sit but still confess anonymously.
The screen may be anything from a curtain to a section of wall with a grille inserted in it. Sometimes the penitent may be able to see the priest through the screen, but the priest can usually never see the penitent. Often placed on the kneeler is a plaque with the Act of Contrition written on it. There may also be other materials associated with the sacrament, such as a card containing the order of the sacrament, with prayers and other useful information. A crucifix or cross might be placed above the screen or anywhere near the penitent to aid in prayer. Many modern confessionals, and even some older, traditional ones, will often have two or three lights outside, which can be controlled by the priest from inside, or are automatic (activated when by the penitent by kneeling on the kneeler or in some other manner). A green light above the priest's location shows that a he is in the confessional and he is available for confession, whereas a red light above the penitent/s area/s shows that it is already occupied and that parishioners should keep away from it so as not to overhear something. If it is necessary to walk by a confessional, it is considered polite to cover one's ear with one's hand, to show respect for the sanctity of the confessional. This is a pious practice even when no-one is in the confessional. In some churches, the confessional is sometimes a room in the church with the screen and kneeler available so it may be used as a confessional, but when no confessions are being heard, the screen can be folded back so it can be used for other purposes.