Flickr Cofounders Launch Slack, An Email Killer

Is the medium the message? Stewart Butterfield on what changes (and doesn't) when we ditch email for good.

Email glut is a big problem for individuals and companies. A recent Symantec Intelligence Report estimates that about two-thirds of all email sent these days is spam. The Radicati Group reckons that 144 billion emails are sent per day, and that’s ignoring mobile users.

Slack, a tool for office collaboration and communication, created by a team of cofounders who designed the web photo-sharing site Flickr, launches today in a preview release. It's meant to reduce or eliminate workplace email, and to compete with services like Yammer and Campfire.

Even if spam filters are getting pretty good at catching the unwanted message, there’s a sense in which all email is basically spam, suggests Slack cofounder Stewart Butterfield. It’s simply more clunky and intrusive than most communications need to be. "It’s the least efficient way to send a message, with the most cognitive overhead," Butterfield tells Fast Company. "If someone I worked with emailed me, I’d probably fire them."

Then again, they should know better by now, having helped create what is meant to be an email killer. Slack presents as a main window for chatting flanked by a bar on the left offering various ways of being in touch; topmost is a list of "channels," or topics. A channel is highlighted in white when you’ve missed out on some of the chatting going on in that channel; a red number is displayed beside a channel if someone has mentioned you by name. Scroll down on the left bar and there are other ways of being in touch, including Direct Message or private groups. It’s ordered top to bottom from the least intrusive ways to communicate to the most intrusive ways to communicate, Butterfield explains.

Slack also integrates various external services, bringing all communications into one interface. So if your organization is addicted to Google Docs, Dropbox, GitHub, Crashalytics, ZenDesk, or other shared services, you can still access them all in one place. Slack doesn’t directly compete with these services, which Butterfield happily says each represent a "15-year slow-motion disintegration of Microsoft’s hegemony over the workplace." He merely wants to make all their messages "searchable, in your pocket" (and indeed, Slack runs on iOS and Android). Slack is "built around search," says Butterfield. Slack features a search bar, so you can pull up a conversation you remember from a while back using a distinctive word or phrase.

This is a larger point than you might initially realize. Because since Slack remembers all communications that were ever had over the platform, it serves as a kind of institutional memory. At a traditional company, a new person getting on-boarded begins with an empty mailbox. But with Slack, this new employee "starts with the entire corpus of organizational knowledge," says Butterfield. You can tell your new hire to catch up on the last week or two of relevant channels. "They would know at the end of that who makes decisions in what domains, who has answers to certain questions—a kind of soft cultural knowledge" about the organization that otherwise takes weeks or months to acquire, according to Butterfield.

At the moment, 45 pilot teams are using the system. Not one has stopped using it, says Butterfield, and he claims that about half have mostly or entirely phased out email. Each organization’s needs and legacy communications are distinct, of course. Butterfield says that one company, Rdio, switched over from Skype IM; Cozy switched over from Campfire and Wantful and Thatgamecompany ditched email, says Butterfield.

And what if you’re attached to email? It might seem odd to get sentimental about a communication that is itself impersonal, but there’s arguably a kind of intimacy that arises from the direct communication and focus that comes with an email. Some people are at their best, communications-wise, when it comes to email—something Butterfield should know intimately. He wrote what deserves to be a canonical resignation letter from Yahoo (which acquired Flickr in 2005) in June of 2008, one that begins: "As you know, tin is in my blood. For generations my family has worked with this most useful of metals. When I joined Yahoo! back in ’21, it was a sheet-tin concern of great momentum, growth and innovation. I knew it was the place for me."

Would there remain room for such acts of performance art in a hashtag-strewn series of chat rooms, I asked?

Butterfield doesn’t hesitate in his response. He says pranks, jokes, and performance of a kind has been a part of Slack’s internal communications before building Slack, and remains so today. He points to an example of he and a cofounder (former philosophy and English grad students, respectively), parodying a Socratic dialogue when introducing a new product to the team. And shortly after our interview, Butterfield sends over an exchange with his team, following an accident he had with a "very aggressively carbonated" bottle of water.

"he is... drying off after an impromptu one-person wet teeshirt contest," wrote a colleague. "(he won)"

Humor follows us wherever we go; the medium is not the message. As the character "Stewart Butterfield" wrote in that Yahoo resignation email: "Who would have thought that Electronic Mail would come to supplant the nation’s own great and venerable post!?"

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  • Patrick Carmitchel

    Real-time is a given and search is a must, but what about context? Email is a problem for teams and our take is a little different at Glip ( We are placing focus on real-time conversation, but also including the tools for teams to manage the natural work lifecycle. Some of that comes from integration, but for conversation to become truly productive for teams, tools like task management and calendar play a vital role.

  • David Gaian

    What is the big deal here?

    How disruptive has Campfire™ or Hipchat™ been?

    Just more tools/options for teams to work as they prefer.


  • Charles Ellis

    By all means write your PR recap / puff piece about this new application, but lets not kid ourselves about this being innovative or anything close to an "email killer".
    The idea of a chat application being better for close collaboration than email hasn't been new for the past 25 years, and Slack is just the latest in a large pile of recently developed commercial chat tools for teams.

  • Claire Lovell

    I highly doubt you are going to get senior management with limited bandwith at any current company to give up on email.  The under 30 crowd, maybe, but not previous generations who find IM to be a constant source of annoying pings all day long.  Not to mention external clients as others have pointed out.  There are literally hundreds of chat services and while this might be a particularly nice one, I haven't had a manager yet who would respond to chat on a frequent daily basis.  

  • Antonin

    Brilliant idea! I can't wait to see the user experience. You have to be amazing if you want to disrupt an usage (replace emails) but it sounds like well started.

    Emails are such a pain in a lot of companies, we're wasting so much times because we don't have a lot flexibility with emails. Also companies are creating a lot of content (procedures, guidelines...) and to keep them well organized can be difficult.

    I can understand the scepticism of some comments - it's a big challenge to replace emails! But if well done, it's gonna be so useful!

  • Greg Macek

    All these types of tools meant to replace email and take it beyond are all interesting, but as mentioned before me they only talk with themselves. What you do with external data from vendors or clients is not clear in the article. 

    My other challenge with this workflow concept is that it seems to place immediacy and "now" as the priority vs. organization and letting us all do things when we want. Email, in its initial form, doesn't imply immediate response though we let it move us that way. IM, by its own name, implies instant. As I keep thinking about to slow people down around my office and get them to stop interrupting my programmers so they can focus on their tasks, tools like this concern me.

    That and search as a solution is only useful when your communications are well written and thoughts are clear. Telling a new hire to go through a stream of IM's an Slack "mail" sounds like a terrible idea. Most of this issue revolves around terrible grammar and clear writing skills that are so prevalent.

    Otherwise, I'd be honestly intrigued to see how well this would work.

  • Meghan O'Dea

    What about, say, if my boss needs to forward me an email from a client outlining how I am supposed to approach a project? Like it or not, separating internal communication just isn't practical. It's like if everyone else can talk to one another out loud, but with one person I'm only allowed to text them.

  • Josh Valentine

    “If someone I worked with emailed me, I’d probably fire them.” - What an a$$hole.

  • Paul Jewkes

    He better fire himself then... To sign up as a user you are required to use an email address. In turn sending yourself an email about the service.
    He invented this. He emailed himself. He should be fired!

  • croncobaurul

     Why in god's name would you want to kill off an open, federated standard of communication (albeit imperfect) for a (presumably) proprietary tool?

  • Le_Post_Monkey

    As an internal tool, I can see the value in something like this.  You'd need to keep the external email, of course, but I like the idea of knowing that everything in my inbox came from the outside world...and my work relationships are maintained in a completely separate space.

    I also like the idea mentioned in the article about getting new hires up to speed by having them search the feeds on their own.

  • croncobaurul

     Fair enough. The proper question is then why would anyone root for them?