The Wales Office (Welsh: Swyddfa Cymru) is a United Kingdom government department. It replaced the former Welsh Office, which had extensive responsibility for governing Wales prior to Welsh devolution in 1999.

In the past it has been called "Wales' voice in Westminster and Westminster's voice in Wales". However, it is significantly less powerful since the Government of Wales Act 2006: it is primarily responsible for carrying out the few functions remaining with the Secretary of State for Wales that have not been transferred already to the National Assembly for Wales; and for securing funds for Wales as part of the annual budgetary settlement.

The Secretary of State for Wales has overall responsibility for the office but it is located administratively within the Ministry of Justice (until 2007, the Department for Constitutional Affairs).

The Wales Office Ministers are as follows:

Unlike Scotland and Northern Ireland, Wales does not have its own Law Officers of the Crown; it is part of the England and Wales legal jurisdiction. The Attorney General for England and Wales therefore advises the United Kingdom Government on its law. His deputy is the Solicitor General for England and Wales.

Wales ⁱ/ˈweɪlz/ (Welsh: Cymru;Welsh pronunciation: [ˈkəm.rɨ] ( listen)) is a country that is part of the United Kingdom and the island of Great Britain,bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km² (8,023 sq mi). Wales has over 1,200 km (750 mi) of coastline, including its offshore islands; the largest, Anglesey (Ynys Môn), is also the largest island in the Irish Sea. Wales is largely mountainous, with its highest peaks in the north and central areas, especially in Snowdonia (Eryri), which contains Snowdon (Yr Wyddfa), its highest summit.

During the Iron Age and early medieval period, Wales was inhabited by the Celtic Britons. A distinct Welsh national identity emerged in the centuries after the Roman withdrawal from Britain in the 5th century, and Wales is regarded as one of the modern Celtic nations today. Gruffydd ap Llywelyn was recognised as King of Wales in 1057. Llywelyn ap Gruffydd's death in 1282 marked the completion of Edward I of England's conquest of Wales. The castles and town walls erected to ensure its permanence are now UNESCO World Heritage Sites. Owain Glyndŵr briefly restored independence to what was to become modern Wales, in the early 15th century. Wales was subsequently annexed by England under the Laws in Wales Acts 1535–1542 since when, excluding those matters now devolved to Wales, English law has been the legal system of Wales and England. Distinctive Welsh politics developed in the 19th century. Welsh Liberalism, exemplified in the early 20th century by Lloyd George, was displaced by the growth of socialism and the Labour Party. Welsh national feeling grew over the century; Plaid Cymru was formed in 1925 and The Welsh Language Society in 1962. The National Assembly for Wales, created in 1999 following a referendum, holds responsibility for a range of devolved policy matters.