| 1947 | Founder, Mizukami, Kunihiko establishes Hakusuisha Inc. (Osaka firm) in Osaka’s Minami-ku. |
| 1954 | Hakusuisha Inc. (Tokyo firm) established in Nihonbashi Kayabacho, Chuo-ku, Tokyo and operation begins with a two-company structure. |
| 1967 | Registered as a construction contractor, registered as a firm with a first-class architect. |
| 1978 | Tokyo and Osaka firms merge (Tokyo and Osaka firms continue to operate under the same trade names). |
| 1981 | Tokyo and Osaka firms change trade names and operation begins with a new structure comprised of the Tokyo Headquarters and Osaka Branch Office. |
| 1985 | Headquarters building completed at current location in Nihonbashi Kayabacho, Chuo-ku, Tokyo. |
| 1991 | Fukuoka Sales Office opened in Chuo-ku, Fukuoka City. |
| 1992 | Building 2 “SENSE” completed next to Headquarters building. |
| 1997 | Celebrated 50 years in operation |
| 2007 | Obtained privacy mark certification. |
| 2014 | Began advertising agency operation. |
| 2015 | Business alliance with NOTION INC. |
| 2016 | Business and capital alliance with A-Plus Design Inc. |
| 2017 | Established Hakusuisha Progress Brains Inc. to enhance and expand our promotion business. | 2022 | Merged with Hakusuisha Progress Brains Inc. | 2023 | Head office relocated to Nihonbashi Kabuto-cho, Chuo-ku, Tokyo |