Harris will focus on developing the consultancy’s work in energy, transport and tech, education, health and social care.
She will work alongside director of public affairs Marc Woolfson and closely with directors in investor services and corporate communications.
Harris joins from Newington Communications, where she spent six years, including as managing partner – when she took over from Nikki Da Costa in 2015 – and most recently as COO, a role she held until the end of 2018.
Prior to that she was managing director of public affairs at consultancy Bellenden, and began her lobbying career at the CBI after working as a journalist.
"I’ve seen how key sectors – such as energy and transport – have come under increasing public scrutiny," Harris said.
"Just look at how the average person is now far more aware of climate change and how more people than ever are actively involved in campaigning – whether that’s through changes in buying habits, community transport initiatives to improve air quality, social media, or participating in Extinction Rebellion protests.
"This growth in public awareness, understanding and activism is not specific to climate change. All businesses must be aware of these shifts in opinion, as well as clearly communicating their views to the public."
WA Communications managing director Dominic Church added: "As issues surrounding sectors such as energy, the environment and transport continue to grow in importance, we want to make sure we’re at the front of these developments. Ensuring that our clients continue to receive high-quality policy guidance, with a modern-day perspective in mind, is integral to our service offering."