Political career
Yeo made his political debut in the 1988 general election as part of a three-member PAP team contesting in the newly created Aljunied GRC and won with 56.33% of the vote against a team from the Singapore Democratic Party (SDP).
Following his election into Parliament, Yeo served in various ministries, including the Ministry of Finance, Ministry of Information, Communications and the Arts, Ministry of Health, Ministry of Trade and Industry and the Ministry of Foreign Affairs.
Yeo represented the Eurasian community in the Cabinet at their request. He was the chairman of the PAP's youth wing from 1991 to 2000, which saw a renaming to Young PAP (YPAP) in 1993. As an incentive for joining the YPAP, he said people joining the YPAP could take positions different from central party leadership.
In 2006, Yeo and the rest of his team faced the Workers' Party (WP) and won with the election's narrowest margin, with 56.09% of the vote to 43.91% for the WP.
However, in the 2011 general election, when Yeo led the PAP team for reelection in Aljunied GRC, Yeo's team was defeated by the WP team of Pritam Singh, Sylvia Lim, Faisal Manap, Low Thia Khiang and Chen Show Mao with WP winning 54.72% of the vote. Yeo was one of the first two cabinet ministers since Singaporean independence, as well as the 1963 election, to be defeated for reelection and thus lose their parliamentary seats to the opposition; the other was Lim Hwee Hua, fellow anchor minister for Aljunied GRC before the 2011 election. As a result, both lost their Cabinet positions as well.
On 10 May of the same year, Yeo announced his retirement from politics. During his announcement, Yeo stated that he declined running for presidency later that year despite being approached by Prime Minister Lee Hsien Loong, cited that he was a "free spirit" and he was not "temperamentally suited for such a job", despite being popular in online and have "a flood of support" on post-election. He although stated on his Facebook page that he was "thinking hard" about the possibility of becoming a candidate on 1 June, but on 15 June, Yeo confirmed that he declined standing for presidency. Yeo later revealed that Lee Kuan Yew had encouraged him to run for the presidency; however, Yeo declined, saying that he "was not going to stand if [Lee] had another candidate in mind".
On 5 October, Yeo stepped down from the PAP's Central Executive Committee. However, he continued to be a member of the PAP.
