Britney has added 20 more shows to her “Circus” tour!

Britney Spears already has the top grossing concert series for 2009 but she has added even more shows.

New dates include stops in New York’s Madison Square Garden and the Mandalay Bay Hotel in Las Vegas. Tickets for the new shows go on sale Friday June 19.

How does she have time to take care of those 2 adorable little boys of hers?