Three more concerts have been planned for the Live 8 charity event - in Japan, Canada and South Africa.
Rock star Bob Geldof, who is organizing the events, says the concerts in Tokyo and Toronto were arranged to put pressure on the Japanese and Canadian governments to increase aid to Africa.
He said now that Europe has agreed to double its aid to Africa, the Americans, Japanese and Canadians have a chance to do so as well.
For the concert in Johannesburg, Geldof said former president Nelson Mandela will open the event, as long as he is healthy enough.
Concerts also are planned in London, Paris, Rome, Berlin and Philadelphia - all on July 2. The goal is to persuade world leaders to increase assistance to Africa.
Some information for this report provided by AP, AFP and Reuters.