London-based Dominiczak will start her position at the ride-hailing company later this month and report to Alex Belardinelli, who was promoted to head of comms for Northern & Eastern Europe earlier this year.
Dominiczak has been a special advisor at the Department for Digital, Culture, Media & Sport since the start of the year. She previously held the same position at the Cabinet Office, the Department for Work & Pensions, and the Department for Business, Energy & Industrial Strategy.
Dominiczak was also media director at Conservatives IN, the Conservative anti-Brexit campaign group, in the run-up to the EU Referendum in 2016.
Her appointment comes as Uber has been taking steps to rebuild its reputation in the UK and elsewhere over accusations around safety and the rights of drivers.
In June the company was granted a short-term licence to operate in London - Transport for London had earlier refused to renew the licence when it expired last September, saying Uber was not a "fit and proper" operator. Uber subsequently made changes, including reporting crimes directly to the police instead of logging criminal complaints with TfL. It also added limits to driver working hours.
Earlier this week, Uber launched a series of safety features in the UK and elsewhere in Europe, including a new ‘safety centre’ where passengers and drivers can share trip details with friends and family.
Meanwhile, Uber is set to appeal a ruling by the Employment Appeals Tribunal later this month relating to the employment status of its drivers.
Hope&Glory started handling consumer PR for Uber and Uber Eats in the UK earlier this year, alongside its consumer and product lead for the UK, Alana Saltzman.