Fox was previously interim director of comms at the Department for the Environment and Rural Affairs (DEFRA), a role she had taken up in June.
She has spent more than 15 years working in government comms and has held senior roles at DEFRA, Department for Business, Energy and Industrial Strategy (BEIS) and the Department of Energy and Climate Change (DECC).
In her new role, Fox reports to Lisa Lee, executive director of communications at WWF-UK.
Lee was head of news at DEFRA before joining the wildlife charity two years ago and told Fox about the job opportunity over the summer.
"It was just too good to pass up," Fox said. "It's an amazing brand to be able to join and the ability of a brand that is that well-known and powerful to help drive change is really exciting and was a massive draw for me."
Words into action
Fox added: "The global climate and nature crises are at the forefront of public debate like never before, and we need to grasp the opportunity to convert that awareness into real action.
"Having spent so much of my time in government working on climate and the environment, I know the power of great communications in making sure these issues stay front and centre."
She described WWF-UK as being "at the heart of driving the change we need in the UK and around the world", and said: "It's an incredible opportunity to join it in that mission."
Fox said her time working in government had given her "an amazing grounding in all parts of communications, from telling proactive, amazing stories to managing some really, really difficult issues and learning how to manage reputation."
Journey to success
Fox worked as a ministerial media adviser in the Australian state of Queensland's government before coming to the UK on a working holiday nearly 15 years ago.
Starting out as a press officer at DEFRA, she spent eight years at the department and rose through the ranks to become deputy head of news and digital communications.
She left DEFRA to join the Department of Energy and Climate Change as head of news and digital comms in 2013. The following year, she became head of media and campaigns.
When the department merged with the Department for Business, Innovation and Skills to create BEIS in 2016, Fox became deputy director, media and campaigns, at the new department.
Two years later she was promoted to its director of comms, before returning to DEFRA earlier this year.
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