May 31 is "World No Tobacco Day". This year's theme is "happy quit smoking, healthy living, being pollution-free citizen". In response to the theme, to help Beijing residents quit smoking, and build smoke-free and green Beijing, the SME 2010 Ph.D. students launched a "World No Tobacco Day" public campaign. On May 31, the students distributed smoking ban brochure on the street, explained the newly-implemented public smoking ban regulation to pedestrians, and introduced the right way and precautions of quitting smoking.