Kelly, who spent six years at Marketing Manchester, will work alongside Zanine Adams at London & Partners who heads up events and business development for the UK.
Kelly has a degree in International Tourism Managing from University of Salford and a postgraduate diploma in Event Management. She also has experience working within inward investment and foreign direct investment at the Manchester Investment and Development Agency Service.
Adams said: "Deborah brings with her a wealth of knowledge and experience from her time at Marketing Manchester. She fully understands the bidding process for events and I’m sure with her support we will go on to secure even more award-winning business events for London.
"I’m thrilled to have joined the London & Partners team at such an exciting time for the capital. London is a world-leading destination which has proven it is the world’s best city for major events with the 2012 Games. I look forward to immersing myself in London and sharing this experience with planners from across the UK."