The Marine Institute has become one of the first State agencies to relocate ahead of the Government's decentralisation programme - but it will still retain a Dublin office.
Some 170 marine scientists and administrative staff have moved into the €50 million purpose-built headquarters at Rinville, Oranmore, on the south-eastern shores of Galway Bay.
However, the institute will still retain its Harcourt Street, Dublin, premises "indefinitely" and a small laboratory facility for use by about 16 staff who will remain on the east coast.
The institute's Dublin-based Irish Maritime Development Office will also stay put, and research facilities at Newport, Co Mayo, will be maintained.
The Galway headquarters and its extensive laboratories - commanding a strategic and spectacular view of the northeast Atlantic - was designed by Ciarán O'Connor, an award-winning architect with the Office of Public Works.
It also includes a creche which accepted its first "clients" yesterday.
The plan for the new premises was approved by former minister for the marine and Galway West TD Frank Fahey, and the first sod for the building, on former Bord Iascaigh Mhara land, was turned by his successor, Dermot Ahern, in September 1994 with a target completion date of November 2005.
A time capsule containing contemporary items, including a copy of The Irish Times, was buried on the new institute's site in 2004 by representatives of more than 120 pupils from local schools.
The Marine Institute is to be opened formally by Taoiseach Bertie Ahern on June 9th. Last week, the €52 million National Maritime College of Ireland was opened at Ringaskiddy, Cork, by Minister for Education and Science, Mary Hanafin.
The college, a constituent college of Cork Institute of Technology, will be run with the Naval Service and was built as a public-private partnership.
Facilities include 270-degree and 360-degree visual ship bridge simulators which can replicate every type of sea and weather condition - and eventualities such as man or woman overboard. It is also equipped with the State's only purpose-built sea-survival training tank.