Murray will take up her new role as comms director on 1 October. She hopes to "redefine" measurement in the charity comms sector, because she believes it is more important than ever for PR to be accountable for delivering a tangible financial return in the charity world.
Murray told PRWeek: "Over the past few years the charity sector has become more commercial, business savvy and entrepreneurial."
Murray has spent the past four years as associate director and partner at Lansons, one of the leading PR agencies in financial services, during which time she also managed public relations at Metro Bank.
She believes her commercially minded approach will be a benefit, but there will also be some inevitable challenges.
She said: "Working for an organisation that has limited resources to put into communications will be difficult but I’m looking forward to it."
She first met the chief executive of Only Connect last year when she was called in to handle the PR coverage of a visit from the Duke and Duchess of Cambridge.
"When I met the team, it reminded me of some of the most impressive entrepreneurial mind-sets I’ve ever encountered," she said.
Only Connect, based in London, delivers six programmes across the City providing training and support for young people at risk of crime, prisoners and ex-offenders.
Murray said: "I’ve always wanted a job where I can walk out of my front door and see how I am making a practical difference. I will be helping people in communities where I have lived and worked."
Murray is also a trustee for the charity Getting on Board, whose aim is to get more people from the commercial sector on to the boards of charities and public bodies.
Murray will not be taking a huge drop in salary but admitted that the earning potential did not match that of the corporate sector.
She said: "It brings other value with it. I think it’s a generational thing – people are realising a job can be enriching in other ways. I wouldn’t have moved from Lansons to another corporate PR agency. This is a different opportunity and I’m really excited about it."