 As an activist, he was instrumental in mobilising mass opposition in 2002 to the Hong Kong Government's Central and Wan Chai Reclamation Project, which was regarded as environmental-unfriendly and a threat to Hong Kong's renown Victoria Harbor.He was behind a judicial review that resulted in stopping the reclamation in Central.In 1994, Cheng co-hosted the ground-breaking political talk show "News Tease" on Asia Television which set the trend of current affairs commentary programmes in the local electronic media.