How Slack Built Its Japan Business: Who Was Hired First and What They Did

Building the Japan business
Written By Murray Clarke

‍ ‍

‍ ‍

Company case study

‍ ‍

Slack hired sellers and customer success in Japan before its country manager. One of those sellers, Shigeharu Fujiwara, has a new GTM book on what that early team lacked.

‍ ‍

‍ ‍Murray Clarke‍ ‍

‍ ‍

‍ ‍

‍ ‍

Slack built its Japan business around demand that was already there. Japanese companies were using Slack before it had a Japanese-language version, one local person was selling before the Japanese company was incorporated, and the country manager, Seiji Sasaki (佐々木聖治), was appointed in February 2018, after the first sellers and customer success work were in place.

One of those early sellers was Shigeharu Fujiwara (藤原茂晴). His first book, on go-to-market (GTM) strategy, was published on 28 September 2026, and its introduction describes what Slack's small Japan team actually did with its time.

If you're a new Japan country manager, or the APAC regional director who'll own the business, the hiring order and his account are both worth a close look. My view is that Slack's order worked because users were already bringing the product into their companies. What I take from Fujiwara-san's book is that demand like that doesn't decide who you sell to, how you sell, or who does what, and that someone has to design those things.

‍ ‍

Japanese companies were using Slack before the Japanese version launched

In April 2017, the CTO of Saison Information Systems published a first-person account of the company's use of Slack. DeNA adopted Slack's Enterprise Grid in October 2017. Both came before Slack had a Japanese-language product.

The Japanese-language version launched on 17 November 2017. Slack said at the time that Japan was already its largest market in Asia Pacific and its third largest in the world by annual recurring revenue. That ranking needs some perspective, though. Slack's annual report for the year to January 2021 says no single country outside the US made up more than 10% of its revenue in any of the three years to January 2021.

‍ ‍

The first hires were sellers and customer success, and the country manager came next

The public record gives a rough order rather than a full roster:

  • Mid-2017: an unnamed local seller started before incorporation, according to Sasaki-san in a June 2018 interview.

  • 2017: customer success work started, set up by a manager who had worked at Box (Customer Success Cafe).

  • December 2017: Fujiwara-san joined as employee number six and the first salesperson focused on small and mid-sized companies. He'd come from telecom sales and from setting up Red Hat's Asia Pacific inside sales team (event biography).

  • February 2018: Sasaki-san was appointed country manager (Mynavi). He had been president of SuccessFactors Japan and head of SAP Japan's Human Capital Solutions business (speaker biography).

  • March 2018: Mizoguchi-san (溝口), who had worked at Microsoft and SAP, joined as Senior Technology Strategist (Mynavi), about the tenth Japan employee by Mizoguchi-san's own count (2019 presentation).

  • Later in 2018: a customer success engagement manager (Customer Success Cafe), a field marketing manager in August, and the first PR manager in Japan (Media Technology).

So Sasaki-san joined a team of under ten people that already had customers, at least two sellers and someone looking after adoption.

‍ ‍

Fujiwara-san spent less than half his time selling

I can read some Japanese, but I'm using AI to help me work through the book, and I haven't finished it yet. What follows comes from the introduction and his notes on the book's website.

His book's introduction goes back to that first year. At Slack's new-hire training in San Francisco in 2017, meeting invitations titled "Japan GTM" arrived on his first day, and he had to look the term up (the book).

Back in Tokyo, he writes, the Japan team was only six people and he was its second salesperson, joining shortly after Slack announced its Japan entry and the Japanese version.

His weeks filled up with other work: speaking at events, detailed feedback to the product team, onboarding customers, finding partners to build API integrations with, trips to headquarters and looking after Japanese customers. Less than half his time went on pure sales activity.

There was no time to draw up a GTM strategy for their own part of the business, so he and the country manager of the time worked through it at a whiteboard. He was thinking about who to focus on, which channels to use and how to grow revenue, but in pieces rather than as one design. In his words, translated: "Looking back, I suppose I was running without a clearly designed GTM strategy."

He says a book laying out GTM strategy would have got him to bigger results sooner with less trial and error, and that he wrote this one for people in the same position today.

‍ ‍

Slack Japan grew quickly between 2018 and 2021

  • June 2018: more than 500,000 daily active users and more than 150,000 paid users in Japan, and a plan for more than 30 staff by the end of the year (ITmedia).

  • March 2019: a dedicated office in Otemachi, Tokyo, with about 30 people (ITmedia).

  • September 2019: Slack's earnings remarks mentioned new million-dollar deals in Japan with a large telco and a large systems integrator, both unnamed (prepared remarks).

  • November 2019: an Osaka office (Slack Japan blog) and a services partner programme naming ABeam Consulting and Ricksoft (Slack Japan blog).

  • February 2020: one million daily active users in Japan, a usage figure rather than paid seats (Slack Japan blog).

  • October 2020: SoftBank started a company-wide rollout, with about 50,000 accounts planned (SoftBank and Slack release).

  • April 2021: Slack told the Japanese press that Japan revenue grew 76% and paid users 79% in the year to January 2021 (Internet Watch).

Salesforce announced its deal to buy Slack in December 2020 and completed it on 21 July 2021. Slack's Japanese company was merged into Salesforce's in December 2021 (gBizINFO, registry history).

Sasaki-san stayed through the integration, leading Slack in Japan and Korea inside Salesforce Japan from October 2021 (speaker biography) and still in charge in March 2023 (Salesforce Japan). He started at OpenAI Japan in June 2024 (speaker biography) and became President and GM of Japan at Factory in August 2026 (Factory). Kazuhiro Ura (浦和広) was publicly named Head of Slack Japan by May 2025 (TerraSky).

Fujiwara-san joined DeepL in April 2022 (his own article), became its first Japan country manager and is now responsible for DeepL's Asia Pacific GTM strategy (publisher).

‍ ‍

Fujiwara-san's book says GTM priorities change as a business grows

The book is 『再現性ある成長のつくり方 「売れる仕組み」を一気通貫で設計するGTM戦略』 (Saigensei aru seichō no tsukurikata: "Ureru shikumi" o ikkitsūkan de sekkei suru GTM senryaku), roughly "How to Build Repeatable Growth: A GTM Strategy That Designs a System That Sells, End to End". Cross Media Publishing published it on 28 September 2026.

He defines GTM as designing, as one consistent whole, who you sell to, what you sell, how you deliver it and how you expand from there. He calls chapters 4 and 5, which cover who sells to which customers and how, the core of the book.

On the book's website, he explains that the priorities change by phase. At launch, the job is to confirm that the product sells, by narrowing down to a few customers and use cases and finding where you win. In the growth phase, the job is repeatability, so that results don't depend on a handful of salespeople. As the business matures, efficiency and growth from existing customers matter more.

He also argues that GTM has been slow to catch on in Japan partly because companies could grow without designing one. I think that describes Slack Japan in 2017 quite well.

‍ ‍

What this means for a regional director hiring in Japan

Slack's order, with sellers and customer success first and the country manager second, suited a product that Japanese users were already bringing into their companies. If your product doesn't have that kind of following in Japan yet, it's a poor model to copy, because your first team will be looking for customers rather than keeping up with them.

That leaves two questions for a regional director.

The first is what your first team actually spends its week on. Ask for the real split between selling and everything else: events, onboarding, product feedback, partner integrations, headquarters calls and travel. A team of six can't do all of it well, so somebody has to decide what comes first.

The second is whether the country manager you hire will design how the team sells or inherit whatever is already there. A country manager who arrives after the first hires, as Sasaki-san did, still has to decide who the team sells to, how, and who does what. At Slack, Fujiwara-san says, that work got done at a whiteboard while he was busy with everything else. The phase matters too. Someone who is good at getting the first sales isn't automatically the right person to make them repeatable, and I've written about those differences in Japan Country Manager Hiring Profile: Builder, Translator, or Caretaker.

Fujiwara-san went from Slack's sixth Japan employee to DeepL's first country manager

Fujiwara-san joined Slack as its sixth employee in Japan in 2017. In 2022 he joined DeepL, where he became its first Japan country manager. More companies coming into Japan should plan for that kind of path.

I've talked about this with a lot of country manager friends across the market, and I see it in my own searches. The people who built the foreign technology business in Japan are a generation ahead of the group coming through now, and there's a gap between the two. Many in the next group are good sellers who haven't yet had the chance to design how a business sells.

Closing that gap means exposing them to GTM practice early: who to sell to, through which channels, and who does what. Books like Fujiwara-san's help. So does working for a leader who explains why the team sells the way it does.

For a company coming into Japan, the experienced country manager you want may not be available, or may not want to run a team of six. Hiring someone earlier in their career and growing them into the role may be your best option, as long as you plan for the support they'll need.

‍ ‍

‍ ‍

Sources

‍ ‍

‍ ‍

‍ ‍

‍ ‍

How this post was researched: the research was produced with AI under Murray Clarke's direction, drawing on Japanese and English press coverage, company releases and filings, Slack's own Japanese blog, and the introduction to Fujiwara-san's book and his notes on its website. Every factual claim links to its source so you can check it. Murray Clarke is accountable for the content.

‍ ‍

‍ ‍

‍ ‍

Research note: AI assisted with research and drafting. Murray Clarke reviewed the analysis and remains responsible for its conclusions. Public sources support the dates and reported results; interpretations of leadership choices are his own. Source links may later become unavailable if publishers move or remove their pages.

Murray Clarke
Next

Akamai, Fastly and Cloudflare: How Late Entrants Compete Against a First Mover