To play this content JavaScript must be turned on and the latest Flash player installed.
Live coverage from the Staples Center, Los Angeles, where thousands of fans have gathered to say goodbye to superstar Michael Jackson.
Artists including Stevie Wonder and Mariah Carey will play at the event.
Roads have been closed off and concrete barriers erected outside the Staples Centre, where Jackson had been rehearsing a comeback show before his untimely death on 25 June.
Other people due to take part in the memorial include Motown boss Berry Gordy, Lionel Richie, Jennifer Hudson, and Britain's Got Talent finalist Shaheen Jafargholi, who has played the young Michael Jackson in the musical Thriller - Live.
The ceremony is due to begin at 1000 LA time (1800 BST).