Laos is divided into provinces (Lao ແຂວງ, pronounced [kʰwɛ̌ːŋ], khoeng, qwang or khoueng) and 1 prefecture (kampheng nakhon) plus the Vientiane Capital city municipality (ນະຄອນຫຼວງ, nakhon louang, or Na Kone Luang Vientiane). The special administrative zone (ເຂດພິເສດ, khet phiset), Xaisomboun, created in 1994, was dissolved on January 13 2006.
While transliterates spelling may differ, the nomenclature used in the 2005 census is as follows: Phongsaly, Luangnamtha, Oudomxay, Bokeo, Luangprabang, Huaphanh, Xayaboury, Xiengkhuang, Vientiane Province, Borikhamxay, Khammuane, Savannakhet, Saravane, Sekong, Champasack, Attapeu, Xaysomboon.
The population of each province in 2005 is given in the census data, ranging from the largest (Savannakhet) to smallest (Sekong).
In 1989 Vientiane prefecture was split from Vientiane province and the capital of Vientiane province moved from Vientiane to Muang Phôn-Hông. In 1994 Xaisômboun khetphiset (special region) was formed from parts of Bolikhamxai, Vientiane, and Xiangkhoang provinces. In 2006 Xaisomboun special region was dissolved and the Longsan, Xaysomboun, Phun, and Hom districts added to Vientiane province, while Thathon district was transferred to Xiengkhuang province.
The provinces are then subdivided into districts (muang) and villages (baan).
The provinces are grouped geographically into 3 strata, North (from Phongsaly to Saiyabouly, Luang Prabang and Xiengkhuang), Central (Vientiane and Bolikhamxay) South (from Khammuane to Champasack).