Mr Charles Garvey is step down as Chief Executive of Horizon Technology at the end of September, and will be replaced by Mr Samir Naji, founder of the company.
Mr Naji already held theposition from the establishment of the group in 1988 until 2001.
Mr Garvey is to stay on the board as a non-executive director.
Mr Naji is currently Horizon's executive chairman and will take over as chief executive on September 30th.
Mr Garvey joined Horizon as operations director in 1989 and was appointed chief executive in 2001.
Over the last year he led a major restructuring exercise that saw Horizon scrap several unprofitable and developmental operations and sell off others, including its Cisco training business.
Earlier this summer, Horizon Technology moved to boost its ailing balance sheet by disposing of a loss-making training business for €12 million.
