Tom Dyckhoff looks at how money is designed to maintain our trust in its value.
Why do so many of us still feel reassured by the pound in our pocket or note in our wallet when most transactions now take place through the virtual balance sheets of a global banking system?
What future is there for global crypto currencies like bit coin or real local alternatives, like the Brixton pound where the notes with the image of David Bowie may soon be worth more than their face value?
Tom meets Victoria Cleland, Chief Cashier of the Bank of England, whose signature is on our UK bank notes - and finds how design features can deter counterfeiters. He also gets a preview of the new polymer notes to be issued in September and visits the Royal Mint who still strike billions of coins a year.
With money and coins little changed over more than 2,500 years, Tom considers a future where the currency of the real world may become a thing of the past.
Produced by Sara Parker
A Falling Tree production for BBC Radio 4.