South Wales Police (Welsh: Heddlu De Cymru) is one of the four territorial police forces in Wales. Its headquarters are based in Bridgend.

Covering Wales' capital city, Cardiff, as well as Bridgend, Merthyr Tydfil, Swansea, and the western South Wales Valleys, it is the largest police force in Wales in terms of population, and the seventh largest in the UK.

The force was formed as South Wales Constabulary (the name was changed in 1996) on 1 June 1969 by the amalgamation of the former Glamorgan Constabulary, Cardiff City Police, Swansea Borough Police and Merthyr Tydfil Borough Police. In 1974, with the re-organisation of local government, the force's area was expanded to cover the newly created Mid Glamorgan, South Glamorgan and West Glamorgan.

In further local government re-organisation in 1996 the force area lost the Rhymney Valley area to Gwent Police. Today it covers the principal areas of Bridgend, Cardiff, Merthyr Tydfil, Neath Port Talbot, Rhondda Cynon Taf, Swansea and the Vale of Glamorgan – most of the ancient county of Glamorgan.

South Wales (Welsh: De Cymru) is an area of Wales bordered by England and the Bristol Channel to the east and south, and Mid Wales and West Wales to the north and west. The most densely populated region in the south-west of the United Kingdom, it is home to around 2.1 million people and includes the capital city of Cardiff (population approximately 324,800), as well as Swansea and Newport. The Brecon Beacons national park covers about a third of South Wales, containing Pen y Fan, the highest mountain south of Snowdonia.

The extent of South Wales is loosely defined, but it is generally considered to be the area surrounding the M4 motorway, including the historic counties of Glamorganshire and Monmouthshire and sometimes extending westwards to include south Carmarthenshire and south Pembrokeshire. In the western extent, from Swansea westwards, local people would probably recognise that they lived in both South Wales and in West Wales — there is considerable overlap in these somewhat artificial boundaries. The northern border is particularly ill-defined, but the A40 may be a good approximation whilst others consider the more southerly Heads of the Valleys Road as the boundary.

This is a list of law enforcement agencies in the United Kingdom. There are a number of agencies which participate in law enforcement in the United Kingdom. There are four general types mostly concerned with policing the general public and their activities and a number of others concerned with policing of other, usually localised, matters.

Over the centuries there has been a wide variation in the number of police forces in the United Kingdom, with a huge number now no longer in existence. See List of defunct law enforcement agencies in the United Kingdom for these.

County police forces traditionally bore the name "constabulary" upon their formation (as a derivation of "constable"). The reorganisation of police forces over the years has seen this name dropped in favour of "police" as a name, as many have decided that the word "constabulary" is confusing for people more used to searching for the word "police". However, a number of police forces in the areas overseen by the United Kingdom retain the name "constabulary":

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.