Diageo plc ( dee-AJ-ee-oh) is a British multinational alcoholic beverage company headquartered in London, England. It is a major distributor of Scotch whisky and other spirits and operates from 132 sites around the world. Diageo-owned distilleries produce 40 per cent of all Scotch whisky with over 24 brands, such as Johnnie Walker, J&B and Buchanan's. Its brands outside whisky include Guinness, Smirnoff, Baileys, Captain Morgan, Tanqueray and Gordon's.

Diageo has a primary listing on the London Stock Exchange and is a constituent of the FTSE 100 Index. It has a secondary listing on the New York Stock Exchange as American depositary receipts.