After working for Hakuhodo, TBWA/HAKUHODO and TBWA/Chiat/Day in Los Angeles, Niizawa joined J. Walter Thompson Japan as Chief Creative Officer in 2019. Awarded ‘Creator of the Year’ by the Japan Advertising Agencies Association in 2014, he also served as a jury member for Cannes Lions 2018 in Film and for Cannes Lions 2022 in Digital Craft.