Inkling has appointed Jono Marcus as its fourth partner and head of digital.
Before joining Citizen last September, Marcus was head of digital at Cake Group. It was there that he worked with Inkling's three other partners, Nicola Rutledge, Will Parkinson and David Proudlock.
Marcus said: 'Myself and the partners at Inkling believe that overturning stale, tired and forgettable marketing strategies takes new and exciting ideas.'
Inkling was launched in 2011 to specialise in PR, events, strategy and content.
In December, it became the global agency for Cutty Sark blended Scotch whisky, owned by The Edrington Group.
The agency's other clients include the Royal Mint and Vintage Festival.
Meanwhile, Citizen has appointed Misha Dhanak, a former associate director at Shine Communications. She joins the agency as a director.