Baker, who resigned as director of DBMT in October, joined the business as director, travel & events at the end of last year and played a key role in the rebrand and move to new offices in East London.
She has also brought on board new clients BNP Paribas Investment Partners, AIMSE Europe, Kwik-Fit and Mercedes-Benz Vans. Other recent account wins include NCP and fonehouse.
Michael Stephens, former DBMT director, travel & events, set up QC Events, formerly Quantum Communications, in 2009.
"Having had a few years out of the events industry on maternity leave, I was keen to come back and get my teeth into the industry again," said Baker.
"I knew Michael had successfully set up his own business, Quantum Communications, so I gave him a call at the end of last year and after several discussions we decided it would be a great idea to work together again."
She added that the agency, which currently has three directors, is now looking to recruit an account manager following the new business wins, and expects revenue to double in 2015.
Stephens commented: "I am delighted to be working alongside Justine again, she has a significant history in delivering live events and performance-improvement strategies across many industry sectors. We work very well together, both bringing different strengths to the partnership, and with Justine on board I am very much looking forward tothe next stage of QC’S journey."