It emerged last week that Joe Lennon, one of Bertie Ahern's closest advisers, is to leave after nine years to become head of communications with the Health Service Executive. His departure is seen as a blow to Ahern, especially coming within a year of a general election.

Lennon was government press secretary for five years between 1997 and 2002, then became special adviser to the Taoiseach after the general election of that year. He was also media director of Ireland's EU presidency.

Last year, former journalist Iarla Mongey, who was the PDappointed deputy government press secretary, left to take up a senior job with top PR firm Drury Communications.

In recent months, several ministerial advisers have also resigned. Dan Pender, special adviser to Martin Cullen in the Department of Environment and then the Department of Transport, left to take a job with the Institute of Taxation.

Tony Cotter, who worked as special adviser with John O'Donoghue since 1997 at both the Department of Justice and the Department of Arts, Sport & Tourism, moved to take a position with the government's official aid programme, Irish Aid . . . formerly known as Development Cooperation Ireland . . . in Limerick.

The other minister to lose a special adviser in recent weeks is Communications, Marine and Natural Resources Minister Noel Dempsey. His adviser, Grace Cappock, is leaving the minister's office to work for leading phone company BT.