All the artists appearing had been winners of the Nordoff-Robbins Silver Clef Award for outstanding contributions to the British Music Industry. Proceeds were split between the Nordoff-Robbins Music Therapy charity and the Brit School of Performing Arts.
Jimmy Page made a "surprise", albeit heavily rumoured, guest appearance alongside Robert Plant.
I've found it quite difficult to pin down a definitive running order of the acts, from Genesis to Elton John in particular, so have gone with the most frequently mentioned order.