The Black Watch, 3rd Battalion, Royal Regiment of Scotland is an infantry battalion of the Royal Regiment of Scotland. The regiment was created as part of the Childers Reforms in 1881, when the 42nd Regiment of Foot was amalgamated with the 73rd (Perthshire) Regiment of Foot. It was known as The Black Watch from 1881 to 1931 and The Black Watch from 1931 to 2006. Part of the Scottish Division for administrative purposes from 1967, it was the senior Highland regiment. It has been part of the Scottish, Welsh and Irish Division for administrative purposes since 2017.

The Royal Regiment of Scotland (SCOTS) is the senior and only current Scottish line infantry regiment of the British Army Infantry. It consists of three regular and two reserve battalions, plus an incremental company, each formerly an individual regiment. However, three regular battalions maintain their former regimental pipes and drums to carry on the traditions of their antecedent regiments.