In 1986 Fujimori formed the Roadway Observation Society with Genpei Akasegawa, Shinbo Minami, Joji Hayashi, Tetsuo Matsuda.

[5] Architectural influences for his work include Le Corbusier, Claude Nicolas Ledoux, Takamasa Yoshizaka, the Ise Shrine and Callanish Standing Stones.

Although the Jinchōkan Moriya Historical Museum has been criticised for merely wrapping a concrete structure in natural materials,[7] it was praised by architect Kengo Kuma as "generating fond feelings of familiarity in people who had never seen it before".

[7] As the theme of the Biennale was the "city" Fujimori included a woven rice twine hut housing a slide presentation of the work of ROJO.

[8] His work with ROJO has left an impression on younger architects like Yoshiharu Tsukamoto and Momoyo Kajima of Atelier Bow-Wow.

[9] In 2018 he served as advisor of exhibition Japan in Architecture: Genealogies of Its Transformations curated by Director of Mori Art Museum Fumio Nanjo[10]

For example, the picture scroll (kakejiku) that normally gives a clue about the time of year is replaced with a large window that frames a view to the town where Fujimori grew up.

It was designed to house works of art by physically disabled children from an institute formed by the Japanese singer and actress Mariko Miyagi in 1967.