THE chief executive officer of ride-sharing business Uber will step down indefinitely as a damning report exposes the company's toxic culture.

Travis Kalanick sent a company-wide email on Tuesday announcing he would take an "unspecified" leave of absence from the company, conceding he needed to improve his leadership skills.

"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," Mr Kalanick said in the memo. His mother died in a boating accident last month.

The San Francisco company has been in meltdown this year, crippled by complaints that it condones sexual harassment, bullying and retaliation against those who make complaints. It has lost nine executives - including one who declined to disclose that he had a sexual harassment complaint levelled against him at his previous job - and it's global program to outwit local authorities trying to shut it down has been exposed.

The 13-page report criticises how the company's "hustlin'" culture had encouraged "poor behaviour", how illicit drugs and alcohol were being used at work events and how the company needed clear policies to combat discrimination and harassment.

The company review was sparked by former Uber engineer Susan Fowler, who published a blog post in February that detailed allegations of sexual harassment, discrimination and retaliation within the company.

She described how her manager propositioned her for sex over the company chat but the Human Resources department dismissed her complaint because he was a "high performer".

Ms Fowler also detailed a cutthroat, win-at-any-costs culture where workers would gain advantage by tearing each other down.

"It seemed like every manager was fighting their peers and attempting to undermine their direct supervisor so that they could have their direct supervisor's job," she wrote.

"It was an organisation in complete, unrelenting chaos."

She also explained how her career progression was hampered because she had made complaints about workplace sexism.

The review, undertaken by US lawyer Eric Holder, essentially takes as read that Uber has significant problems with its workplace culture and offers 10 detailed recommendations on how to fix it.

The report zeros in on the company's 14 existing values, which it says have "been used to justify poor behaviour".

The review urged the company to junk its prescribed values, which include Always Be Hustlin', Meritocracy, Toe-Stepping and Principled Confrontation.

They represent the hyper-competitive, take-no-prisoners mentality that has helped the company cripple the taxi industry and become the world's top start-up, valued at $US70 billion.

But the report reveals that the great success has bred a toxic culture.

The key recommendations include:

● Cut back Travis Kalanick's responsibilities: The report suggests sharing or reallocating the CEO's responsibilities to other senior managers.

● Promote diversity and inclusion: The report stresses the need for practical hiring processes to encourage the employment of women and people of diverse backgrounds, and to ensure they are included and promoted.

● Hold senior leaders accountable: It suggests doing this through performance reviews and financial incentives. It also encourages the company to establish formal leadership training that can "combat implicit bias" and "encourage a culture in which everyone gets heard in a manner in which they are comfortable and employees feel safe to propose ideas".

● Sort out complaints process: It encourages providing a number of avenues for people to complain about bad behaviour without having to report it directly to their managers or the CEO. "Uber should consider adopting a zero-tolerance policy for substantiated complaints of discrimination and harassment, without regard to whether an employee is a 'high performer' or a long-term employee," the report reads.

● Discourage use of alcohol and illicit drugs at work: "Uber should take steps to provide clear guidelines about acceptable and unacceptable uses of alcohol and strictly prohibit the use of controlled substances, including prohibiting consumption of alcohol during core work hours and prohibiting consumption of non-prescription controlled substances during core work hours, at work events, or other work-sponsored events," the report reads.

The Uber board has agreed to adopt all of Mr Holder's recommendations.

Mr Kalanick, 40, has earlier acknowledged that he needed to "fundamentally change and grow up".

He was exposed on a dashcam video earlier this year that showed him verbally abusing an Uber driver who had complained about making less money from the platform.

"I'm bankrupt because of you," the driver says in the video published by Bloomberg.

"Bulls**t," Mr Kalanick yells repeatedly before slamming the car door behind him.

The CEO also copped criticism in 2014 when he told GQ that he referred to Uber as "Boob-er" because it helped him attract women.

News Corp Australia

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