Castellana will join the senior team of the 60-strong property unit, which is headed up by group managing director Andrew Jack.
She brings more than 15 years of comms experience at agencies including brand communications property specialist Socrates, and luxury agency Luchford, working across business, lifestyle, trade and luxury sectors.
Four’s property business is reports £6.5 million in annual fee income, and clients include Clarion Housing Group, Grosvenor UK & Ireland, and Southbank Tower.
The agency has also promoted Geoff Robjent to director in property. Robjent joins the Property Board and is a trained journalist with more than seven years of experience in built environment communications.
Group MD Andrew Jack said: "We are pleased to have Lindsay on board. Her international cross-sector expertise will, in particular, strengthen our property PR offering and our senior team across the property business unit.
"As one of the leading agencies in property marketing and communications we are always keen to welcome people with deep sector knowledge and a love of the industry."