The houngan is a male priest of Haitian Vodou, the head of a temple and of the family of initiates and worshippers attached to it.
What the office does
Publicly the work of the houngan is plainly described: he leads ceremonies, is served by the lwa, the spirits, treats illness and misfortune, divines, prepares remedies, and is the person a family turns to when something has gone wrong that has no ordinary explanation. He maintains the temple and its altars and initiates others into the tradition. The initiation, the kanzo, is closed.
Authority without a hierarchy
Authority in Vodou is decentralised. There is no rank above the individual houngan, no national body, and no one who can strip a priest of standing except the community that stops coming to him. The houngan and the mambo, the female priest, hold the same office and the same authority; gender does not distinguish the two in function, which is worth stating plainly given how the religion is usually depicted. Vodou has been an officially recognised religion in Haiti since 2003.