Uber Technologies Inc said said on Wednesday that the ride-hailing firm has appointed Barney Harford as chief operating officer, as the company looks to fill positions left vacant after key staff quit in recent months.

Harford, a former chief executive officer of online travel website Orbitz, will join Uber on Jan.2, Uber said in a statement.

Uber is facing a host of problems, including allegations of sexual harassment, data privacy violations, and a criminal investigation over alleged trade-secrets theft.

New CEO Dara Khosrowshahi, who replaced co-founder Travis Kalanick in August, has been critical of past practices and vowed a new era of compliance.