Lyon & Turnbull is a privately owned international auction house located in Scotland.

The company is the largest independent auction house in the United Kingdom outside of London.

They were joined in the enterprise by Sir Angus Grossart, Chairman of Noble Grossart, a Scottish merchant bank, and a past chairman of the trustees of the National Galleries of Scotland.

The company's stated aim was "to rescue a national institution for Scotland and to establish a high quality auction house with an international footprint from a base in Edinburgh".

[1] The firm has a transatlantic alliance with the United States' oldest auction house, Freeman's of Philadelphia.