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OFFICES › MINATO, TOKYO › MITSUI KNOWLEDGE INDUSTRY

Office · Minato, Tokyo · IT

Mitsui Knowledge Industry — Omotesando: a ten-floor head office designed around the space “in between”

Mitsui Knowledge Industry brought three Tokyo sites into one building near Omotesando in 2026. The concept is “/ in between”: innovation happens where different things meet. Floors two to four are for exchange — a mirrored ceiling that opens to the street, a square of pink and orange, and a “big meadow” with a bar, a camp and a library — and the work floors above are coloured red, green and blue.

Company Mitsui Knowledge Industry Co., Ltd. (三井情報株式会社) ↗Location Minato, Tokyo (Omotesando)Completed February 2026Area 11,042 m²Staff About 1,900Floors 2F–4F exchange areas; 5F–10F work areasSeating Group addressDesign ITOKI — concept, design and construction
The entrance
The entrance

Concept

/ in between

The company’s own building had aged, and it wanted to merge three sites in Tokyo into one, sharing knowledge across the organisation. After its own staff workshops on ways of working, it chose a “group address” system.

Innovation is often said to come from combining existing ideas. The concept “/ in between” puts that in space: different knowledge and people meeting across a slash. It matches the company’s purpose, “connecting with knowledge, creating the future”. Each floor has its own pair — region and company, on and off, organisation and individual — and the floors are deliberately not uniform.

The stair
The stair
The building at night
The building at night

01 · 2F

Open to the street

The second floor is about connection with the outside. With Omotesando in mind, it uses materials of the street — tile, plaster, steel. A mirrored ceiling lets views cross between inside and out; it was chosen after repeated simulations of how it would look from outside and how the light would fall in each season.

The entrance is big enough for events, seminars and pop-ups, and display stands were made from envelopes printed with the old logo, upcycled when the logo changed.

The mirrored ceiling
The mirrored ceiling
The street side
The street side
Planting and tables
Planting and tables
A pallet bench
A pallet bench

02 · 3F

A town square and lanes

The third floor is imagined as a town square and its lanes, with pink and orange and many patterns of furniture so everyone can find a favourite place. Art representing the organisation carries the company’s message, and there is more wood than on the floor below.

The organisation artwork
The organisation artwork
The artwork
The artwork
Shelves and seats
Shelves and seats
A corner
A corner
Pink chairs
Pink chairs

03 · 4F

A meadow with no rooms

The fourth floor is a “big meadow” where on and off coexist, with no private rooms at all. BAR, CAMP, PARTY and LIBRARY share one floor, to be used like choosing a favourite piece of playground equipment. Three panel artworks carry a message to staff: “create the future”.

TSUDOI CAFE
TSUDOI CAFE
The bar counter
The bar counter
A high table
A high table
A planted counter
A planted counter
Soft seating
Soft seating
Tables
Tables
A striped installation
A striped installation

04 · 5F–10F

Red, green, blue

The standard work floor is repeated on six floors, each assigned one of the three primary colours of light — red, green and blue — the basis of colour on a screen. The interior is kept minimal; furniture from five brands was compared and combined like a puzzle.

A meeting room
A meeting room
Booths
Booths
A booth
A booth
A meeting room
A meeting room

05 · Afterwards

Events, visitors, applicants

The company says in-house events have started from the fourth-floor café bar, more clients ask to visit, and job applications have risen.

A lounge
A lounge
Platforms
Platforms
A work lounge
A work lounge
Planting
Planting
Bench seating
Bench seating
A striped wall
A striped wall
CompanyMitsui Knowledge Industry Co., Ltd. ↗
DesignITOKI Corporation
Photography© ITOKI Corporation (from ITOKI WORK-Style Design)
SourceITOKI WORK-Style Design, project page, re-reported by WALL ↗
PublishedOctober 2026
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