A new central firearms unit, known as Special Tactics and Operational Command, is now up and running.
STOC takes over the responsibility of the elite Emergency Response Unit and will liaise with divisional commanders regarding the use of regional Armed Support Units.
The command assumes responsibility for all firearms policy and training and will also house the highly skilled negotiators who deal with armed barricades or sieges.
The ERU, and the negotiators, are being taken out of the Special Detective Unit.
STOC will come under the authority of the Assistant Commissioner Crime & Security, Michael O'Sullivan.
Chief Superintendent Gerry Russell, a former head of the ERU, has been appointed as head of STOC.
He is leaving as the head of the Security and Intelligence Section at GardaHeadquarters.
This section is the intelligence gathering arm of the force and also liaises with foreign security and police agencies.
Chief Supt Tom Maguire, is leaving as boss of the Special Detective Unit, to take over the S&I section.
The SDU, based in Harcourt Square, is the operational arm of the security service and targets both dissident terrorist groups and international terrorism.
The new head of the SDU is Chief Supt Tony Howard, one of the five new chief superintendents appointed by the Policing Authority since June.
Chief Supt Howard was promoted from detective superintendent at the Drugs and Organised Crime Bureau, which has secured mounting success against the Kinahan crime cartel within the last year.
Of the other four newly promoted chief superintendents:
*Cliona Richardson (formerly National Criminal Intelligence Unit) is taking over at Liaison & Protection in the Crime and Security branch at Garda HQ
*Finbarr Murphy (formerly of Ballymun, Dublin North) assumes the head of the GardaNational Roads Policing Bureau
*Colette Quinn (formerly Community Relations Bureau) takes over as divisional officer for Cavan/Monaghan
*Michael Daly (formerly Protective Services Bureau) is the new divisional officer for Dublin East
The Louth Division has been taken over by Chief Supt Christy Mangan, who moves from the Cavan/Monaghan Division.