SThree's chief operating officer is to retire at the end of the current financial year after more than 22 years at the recruitment firm.Sunil Wickremeratne, who took up his latest role in 2004, will leave the company at the end of November to ensure an orderly handover of his responsibilities, which will be divided between existing executives."While we will miss his input around the board table, we fully understand his desire to retire while he is still young enough to enjoy life to the full," said boss Russell Clements.