History
| June 1900 | Foundation of Sumitomo Temporary Architecture Department |
|---|---|
| May 1933 | Hasebe and Takekoshi independently established HASEBE-TAKEKOSHI ARCHITECTS OFFICE, funded by Sumitomo Limited Partnership Corporation |
| December 1945 | Renamed as Nippon Engineering Co., Ltd. (predecessor of today’s Sumitomo Corporation). The Trading Department was newly established after merging with all Sumitomo dealers. |
| July 1950 | Design Department of Nippon Engineering Co., Ltd. spun off to establish Nikken Sekkei Komu Co., Ltd. |
| July 1970 | Renamed to Nikken Sekkei Ltd. |
| August 1998 | Establishment of Nikken Sekkei PMC (Property Management Consulting) Office |
| March 1999 | Establishment of Nikken Sekkei CM (Construction Management) Office and PM (Project Management) Office |
| February 2001 | Establishment of Nikken Sekkei FMS Office |
| March 2001 | Establishment of Nikken Sekkei Management Solutions, Inc. (NMS) |
| April 2003 | Establishment of Nikken Sekkei Value Management Office |
| January 2004 | Establishment of Nikken Sekkei Value Management/Engineering Department. Unification of Tokyo and Osaka. |
| January 2005 | Establishment of Nikken Sekkei Construction Management, Inc. |
| December 2019 | Licensed Real Estate Brokerage (Governor of Tokyo（1）#104228) |
| July 2021 | Establishment of Kyushu Branch |