The Company is progressing its search for her successor as Chief Executive using the services of Egon Zehnder International.
Until a permanent appointment is made the duties of the Chief Executive will be assumed by the Group Finance Director, Vijay Vaghela who will work closely with the newly appointed Chairman David Grigson.
David Grigson said: "The Company and the Board are grateful to Sly for her immense contribution and leadership over nearly 10 years. Despite the deep economic downturn, the actions she has taken with her team have ensured the Company has consistently delivered robust profits. We wish her well for the future."
Sly Bailey (pictured) said: "Newspapers are a business like no other and it's been an absolute privilege to have led Trinity Mirror in this fascinating and all-consuming role. Everything I've achieved during my time here has been underpinned and supported by the hard work, commitment and enthusiasm of our tremendous staff."