From today very fortunate street collectors will notice a new design for the £50 note, featuring the 18th century business partnership of entrepreneur Matthew Boulton and engineer James Watt. It is the first time two portraits have appeared together on the reverse of a Bank of England banknote.
Boulton and Watt were pioneers in using the steam engine in the cotton spinning industry.
It is the second in the Bank of England's Series F 'family' of notes which began with the introduction of the Adam Smith £20 note in 2007. It features a range of new and enhanced security features.
The signature on the banknote is new too. It is the first banknote to be signed by Chris Salmon, who was appointed as the Bank's Executive Director - Banking Services and Chief Cashier in April 2011.
As at the end February 2011, the value of £50 banknotes in circulation was £9.9 billion.
Previous banknotes include the the Houblon Series E £50 note, introduced in 1994; the Sir Christoper Wren design, introduced in 1981 and withdrawn from circulation in 1996; and the white £50 in issue between 1725 and 1943.