Chiam See Tong is a Singaporean retired politician and lawyer who served as the Secretary-General of Singapore Democratic Party (SDP) between 1980 and 1993 and Secretary-General of Singapore People's Party (SPP) between 2011 and 2019 and the chairman of Singapore Democratic Alliance (SDA) between 2001 and 2011. He was the de facto Leader of the Opposition when he became the Member of Parliament (MP) for Potong Pasir Single Member Constituency (SMC) and served between 1984 and 2011.

The Singapore Democratic Party is a social liberal political party in Singapore. Having peaked at three seats after the 1991 general election, the party currently has no seats in Parliament since 1997.