Tan Cheng Bock is a Singaporean politician and former Member of Parliament. He served in the People's Action Party (PAP) from 1980 to 2006, representing the Ayer Rajah constituency. Known for his medical background as a trained doctor, he has been involved in various public health initiatives throughout his career. In 2011, Tan Cheng Bock ran for the presidency of Singapore but was ultimately defeated by Tony Tan. He later announced his intention to contest the 2017 presidential election, which was open only to candidates from specific backgrounds. His political journey has made him a notable figure in Singapore's political landscape.