System of a Down will be will be co-headlining Rock In Rio concert with Guns n' Roses, on Sunday October 2, 2011. According to SOAD official website, the tickets for Brazil-hosted concert were sold out.

SOAD announced its reunification in November 2010 after five years of inactivity, saying it will tour Northern America and Europe. Prior to that Serj Tankian had performed solo concerts, while Daron Malakian and John Dolmayan created Scars on Broadway band.