stewart butterfield

By all measures, Slack is one of the fastest growing startups in Silicon Valley.

More than 1.5 billion messages are sent monthly on the platform. 2.3 million people use it daily, and of those, 20% just started using it in the new year.

Its CEO Stewart Butterfield isn’t worried about the product — it’s clearly been proven a hit.

Instead, he told the crowd Wednesday at the Startup Grind conference that he’s most worried about the people.

At the beginning of 2015, Slack employed around 80 people. By year-end, that number ballooned to 320 employees. Already in 2016, the company has increased its headcount to 385. (That’s adding at least one employee every day.)

“The thing I worry about is people,” Butterfield said. “That kind of growth is hard to do.”

It’s a crazy rate of growth, but it’s justified to keep up with demand, Butterfield argues.

The bigger issue is how to integrate all of the new employees into Slack’s culture so they’re there for more than just the valuable stock options.

“You need to really have the volume up. Cultural problems need to be addressed as they arise,” Butterfield says.

Turning the volume up means constantly, and loudly, reiterating the company’s values and making sure they don’t get muddled as the company grows.

The company has six core values, expressed in three sentences, Butterfield explains:

  1. Empathy as expressed through courtesy
  2. Craftsmanship tempered with playfulness (That’s where those funny Slack messages come from)
  3. Thriving, both in ourselves and others (That means thriving not only as a team, but also making sure you’re personally thriving and doing this thing you’re meant to be doing with your whole heart, Butterfield explained)

Making sure those are understood and embraced is a challenge for a company growing so rapidly, but one that Butterfield is making a priority to address early as it grows — and not just when it’s too late.

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