|1901||Hoshiro Mitsunaga establishes Japan Advertising Ltd. and Telegraphic Service Co.|
|1906||Telegraphic Service Co. becomes Japan Telegraphic Communication Co., Ltd.|
|1907||Japan Advertising Ltd. merges with Japan Telegraphic Communication Co., Ltd. and starts to engage in communication and advertising operations.|
|1936||Japan Telegraphic Communication Co., Ltd. relinquishes its news services department to Domei News Agency and re-launches itself as a specialized advertising agency.|
|1940||Shinzo Mitsunaga becomes the second President.|
|1943||The Company acquires 16 companies in a move to augment its advertising agency business. Operational bases are established in Tokyo, Osaka, Nagoya and Kyushu.|
|1945||Sekizo Ueda becomes the third President.|
|1947||Hideo Yoshida becomes the fourth President.|
|1948||Creation of the Dentsu Advertising Awards.|
|1949||Creation of the Dentsu Advertising Essay Contest for Students.|
|1951||Dentsu establishes the Radio Division at its Head Office and local offices. Commercial radio broadcasting begins in Japan.|
|1953||Dentsu creates the Radio and Television Division at its Head Office and local offices. Commercial television broadcasting begins.|
|1955||Dentsu Advertising Ltd. becomes the new company name.|
|1963||Tsuneji Hibino becomes the fifth President.|
|1967||Completion of Tsukiji Head Office Building.|
|1973||Yoshichika Nakahata becomes the sixth President.|
|1974||Advertising Age ranks Dentsu No. 1 advertising agency worldwide in terms of (calendar 1973) billings.|
|1977||Hideharu Tamaru becomes the seventh President.|
|1981||The company formerly known as JIMA Dentsu Advertising, Ltd. and U.S. partner Young & Rubicam's Japanese affiliate establish Dentsu Young & Rubicam as a joint venture in Tokyo.|
|1984||Dentsu and U.S.-based Young & Rubicam jointly establish DYR, an international service network.|
|1985||Gohei Kogure becomes the eighth President.|
|1988||Advertising Age names Dentsu the 1987 "International Agency of the Year."|
|1989||Fiscal 1989 billings exceed 1 trillion yen.|
|1993||Gohei Kogure becomes the first Chairman. Yutaka Narita becomes the ninth President.|
|1995||Dentsu establishes five domestic regional subsidiaries.|
|1996||Japan-China Advertising Education Exchange Project commences. Dentsu Tec Inc. is established.|
|2000||Dentsu makes an equity investment in the Bcom3 Group. Information Services International-Dentsu, Ltd. lists its shares on the First Section of Tokyo Stock Exchange.|
|2001||Dentsu lists its shares on the First Section of Tokyo Stock Exchange. Dentsu commemorates its 100th anniversary.|
|2002||Yutaka Narita becomes the second Chairman. Tateo Mataki becomes the 10th President. The Bcom3 Group merges with Publicis Groupe S.A. Dentsu acquires a 15% stake in the newly formed group. Dentsu's new Shiodome Head Office Building opens in November.|
|2003||Dentsu East Japan Inc., Ad Dentsu Tokyo Inc. and Dentsu Tohoku Inc. merge, with Dentsu East Japan as the surviving company.
Geneon Entertainment Inc. and Geneon Entertainment (USA) Inc. are converted to subsidiaries.
|2004||Tateo Mataki becomes the President & CEO.
Dentsu Group initiates the UNESCO World Terakoya Movement "kururimpa" project.
|2005||Dentsu Group obtains BS7799 certification and Information Security Management Systems (ISMS) certification.
All of Dentsu's domestic branch offices receive ISO 14001:2004 certification.
|2006||Dentsu Tec is converted to a wholly-owned subsidiary, and its shares are delisted.|
|2007||Dentsu Group achieves consolidated billings (net sales) of 2 trillion yen.
Tateo Mataki becomes the third Chairman. Tatsuyoshi Takashima becomes the eleventh President.
|2008||Dentsu establishes an internal committee for the deliberation of environment-related strategies.
Dentsu receives "Eco-First Company" certification.
|2009||Dentsu announces the new Dentsu Group corporate philosophy: "Good Innovation."
Dentsu introduces the "Director, Member of the Board & Executive Officer" management system.
cyber communications inc. becomes a wholly-owned subsidiary.
Dentsu Announces New Medium-Term Management Plan "Dentsu Innovation 2013".
|2010||Dentsu establishes Dentsu Digital Holdings.
Dentsu establishes Dentsu Network West.
|2011||Tatsuyoshi Takashima becomes the fourth Chairman. Tadashi Ishii becomes the twelfth President & CEO.|
|2012||Dentsu establishes the Dentsu Network, an umbrella organization of the Company's agencies outside Japan. Dentsu Network West is absorbed into the Dentsu Network.|
|2013||Dentsu acquires Aegis Group plc and establishes a new global operating unit, Dentsu Aegis Network Ltd., in London.|
|2014||Dentsu Appointed as Marketing Agency by the Tokyo Organising Committee of the Olympic and Paralympic Games.|
|2017||Toshihiro Yamamoto becomes the thirteenth President & CEO.|
|2020||Transitioned to a new holding company structure, and Toshihiro Yamamoto became the first appointed to Dentsu Group Inc.
Hiroshi Igarashi was appointed the 14th President of Dentsu Inc.