Answer
Atambayev served as Chairman of the Social Democratic Party of Kyrgyzstan from 30 July 1999 to 23 September 2011. He was first elected as Chairman of the party in 1999 and was re-elected in 2004 and 2009. During his time as Chairman, the party became the largest opposition party in Kyrgyzstan. Atambayev resigned as Chairman of the party in 2011 after being elected President of Kyrgyzstan.