Sir Elton John has signed a deal to publish "the very personal story" of how Aids affected his life.
The book, which will be called Love is the Cure: Ending the Global Aids Epidemic, will include his memories of friends including Queen frontman Freddie Mercury who died of an Aids-related illness in 1991.
Sir Elton said: "This is a disease that must be cured not by a miraculous vaccine, but by changing hearts and minds, and through a collective effort to break down social barriers and to build bridges of compassion. Why are we not doing more? This is a question I have thought deeply about, and wish to answer - and to help change - by writing this book."
Money raised by sales of the book will go to his charity Aids foundation. Set up 1992, EJAF has raised more than $225m (£146m) to support projects in 55 countries around the world. It is estimated that 33 million people worldwide live with HIV.
The book, described by publishers Hodder and Stoughton as "the very personal story of Sir Elton's life during the Aids epidemic", will be published to coincide with an international Aids conference in Washington DC in July, along with an audio book read by Sir Elton.
The star and his civil partner, David Furnish, became parents of a son, named Zachary, via a surrogate in 2010.