His leave comes on the same day a report on the company's culture was released.
Yahoo Finance obtained leaked audio of this exchange between board members Arianna Huffington and David Bonderman during Uber's staff meeting Tuesday.
"There's a lot of data that shows when there is one woman on the board, it's much more likely that there will be a second woman on the board," Huffington said in the recording.
"Actually, what it shows is there's more likely to be more talking," Bonderman is heard saying in response.
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"Ooh, come on David. Don't worry, David will have a lot of talking to do as well," Huffington said after.
Bonderman has already started talking in the form of an apology for his "disrespectful" comment. "I also want to apologize to all Uber employees who were offended by that remark, I deeply regret it," he said.
That exchange has gone viral because it highlights a culture already under scrutiny at Uber.
"They seem to take that stereotype of male-centric, male-dominated, not very diverse and amp it up 20 degrees from every other company out there," New York Times technology reporter Mike Isaac said.
He said the culture helped give the ride sharing company a global footprint, but it's also resulted in terrible public relations along the way.
Now investors in the $70 billion company are shaken. "I've been talking to a lot of investors over the past few weeks and a lot of them are kind of freaked out right now," Isaac said.
Uber asked former Attorney General Eric Holder to investigate the culture after a former Uber employee went public with her experience of sexual discrimination and harassment.
Holder's report was released on Tuesday, with 47 recommendations ranging from more diversity hires to more manager training to earlier dinner delivery.
MORE: See full list of Uber recommendations here
"The fact that the board unanimously voted to approve all these recommendations is significant. It means they really do want to change," CNET reporter Dara Kerr said. "We'll have to wait and see if that happens."
The first recommendation was reducing Kalanick's responsibilities. He took it to heart, announcing his leave of absence in a company-wide email so he can grieve his mother's sudden death and work on his leadership skills.
Kalanick says there is no timeline for his return.
Kalanick sent this memo to staff:
For the last eight years my life has always been about Uber. Recent events have brought home for me that people are more important than work, and that I need to take some time off of the day-to-day to grieve my mother, whom I buried on Friday, to reflect, to work on myself, and to focus on building out a world-class leadership team.
The ultimate responsibility, for where we've gotten and how we've gotten here rests on my shoulders. There is of course much to be proud of but there is much to improve. For Uber 2.0 to succeed there is nothing more important than dedicating my time to building out the leadership team. But if we are going to work on Uber 2.0, I also need to work on Travis 2.0 to become the leader that this company needs and that you deserve.
During this interim period, the leadership team, my directs, will be running the company. I will be available as needed for the most strategic decisions, but I will be empowering them to be bold and decisive in order to move the company forward swiftly.
It's hard to put a timeline on this - it may be shorter or longer than we might expect. Tragically losing a loved one has been difficult for me and I need to properly say my goodbyes. The incredible outpouring of heartfelt notes and condolences from all of you have kept me strong but almost universally they have ended with 'How can I help?'. My answer is simple. Do your life's work in service to our mission. That gives me time with family. Put people first, that is my mom's legacy. And make Uber 2.0 real so that the world can see the inspired work all of you do, and the inspiring people that make Uber great.
See you soon,
To read more about Uber, click here.
Uber's CEO @travisk sent company wide email : he's taking time off to grieve his mom, his direct reports will act as a team to run company— Tiffany Wilson (@TWilsonTV) June 13, 2017