Formerly a journalist on Accountancy Age and then the Sunday Times and Mail on Sunday, she then held senior roles in the corporate teams of agencies MHP and FTI Consulting.
Kemeny then worked for British American Tobacco for seven months to January 2017 and held an interim post at EY before joining Terra Firm this month.
She said: "I am delighted to have joined Terra Firma as head of communications where I am in the privileged position of working for one of the most differentiated private equity funds in the world."
The firm, which has invested €17bn in 33 business over its 24-year history, has current investments including Four Seasons Health Care, Wyevale Garden Centres and Italian solar energy firm RTR.
Its largest previous investments were in German housing firms Deutsche Annington and Viterra, with the latter later merged into the former.
Alongside Kemeny, the firm lists Finsbury managing partner Rollo Head as its European media contact, and Jonathan Doorley of Sard Verbinnen & Co for the US - although Doorley has recently joined Brunswick, according to LinkedIn.
A previous incumbent of the role, Christen Thomson, now works for the agency Citigate Dewe Rogerson.