All of John Lennon's solo catalogue is to be made available to buy in digital download form by the end of the year.
Lennon's greatest hits are already available to download
The greatest hits double album Working Class Hero can already be purchased and will be followed next month by the rest of the former Beatle's solo material.
Yoko Ono, Lennon's widow, said she was "very happy that John's music is now available to a new generation of fans".
"New technology is something he always embraced and this is something he would have loved," she continued.
"I think it's important that we remember John for what he contributed to the world.
"For people who still love John's music and for those now getting into John's music, this opens up a whole new world in which they can appreciate it again."
Fans can download Lennon's solo work from 5 December in the UK and from the day after in the US via legitimate digital music services.
They will also be able to download a selected number of his tracks onto mobile phones, from a later date.