This document summarizes the advertising work of Yi Jeseok. It discusses three of his most notable works: "A chimney can be a gun" which contained an air pollution warning message and won a Gold Pencil award; "What goes around, comes around" which was a pro bono public service campaign to support peace; and "Complaint laid a creativity" about the difficulties of subway stairs for those with disabilities. The document provides background on Yi Jeseok but does not go into detail about his career or influence. It lists additional works and cites sources for further information.