He replaces outgoing chairman Stephen Knight, who has chaired the board since 2008.
It follows a series of appointments at Cicero as it expands its offering. Earlier this year it opened a new healthcare practice headed by former Baxter senior comms director Fiona Cohen. More recently, Sky News executive producer Kate McAndrew joined as a senior counsel working in its corporate PR and public affairs practices.
Jeremy Swan, Cicero CEO, said: "In Iain we have a dedicated, inspiring leader and one of the top industry figures of his generation. I can think of no better person to lead the board as we enter the next phase of growth and strategy. I would also like to place on record my enormous gratitude to Stephen Knight for his immense contribution to the Cicero story."
Anderson said: "Having recently moved to our newly designed headquarters in the City and with our growing global blue chip client base, I am thrilled to be leading the Cicero Board at one of the most exciting times in our development."
Speaking to PRWeek in February, Swan said: "We are an entrepreneurial company and we want to expand. Once we have bedded in healthcare, we will most certainly be looking at other markets and sectors, absolutely."