Fitzgerald stepped down as Wexford hurling manager 12 months ago and has spent the last year as coach to the Cork camogie team, having been strongly considered for the Galway management position before Henry Shefflin's appointment last October.
Fitzgerald, who stepped down as Waterford manager after three-and-a-half years in charge in 2011, will take over from Liam Cahill.
Cahill was Waterford manager for three years but has moved back to his native county in recent weeks, following Colm Bonnar's departure in Tipperary.
Fitzgerald's appointment is sure to divide opinion in Waterford but his record of firing up teams in the early part of his reign is impressive and within three years in Waterford, Clare and Wexford he had won at least a provincial title or in Clare's case, an All-Ireland.
He was the recommendation of a four-man committee, county board chairman Sean Michael O'Regan, secretary Pat Flynn, CEO of Nemeton TV Irial Mac Murchú and former Waterford captain Fergal Hartley, and in keeping with appointments in Cork, Tipperary and Kilkenny, they have moved quickly, getting approval from a county board meeting tonight.
It comes as Liam Sheedy and Eamonn O'Shea are linked with the vacant Offaly hurling position.
In a surprise move, reported by the Irish Mirror, Offaly GAA are understood to be keen on reuniting Sheedy and O'Shea, manager and coach when Tipperary won All-Ireland titles in 2010 and again in 2019.
Offaly will be a Joe McDonagh Cup team again in 2023 but there is some promise there.
If it comes off the Sheedy/O'Shea ticket would replace Michael Fennelly, who departed two weeks ago but the suggestion is that Johnny Kelly, who worked with Fennelly, would be staying on.
Sheedy has worked with teams other than Tipperary before, most recently spending time as performance coach with the Monaghan footballers for a year. He has also advised Antrim hurling in the past.
For Fitzgerald, the appointment means a 37th consecutive year of inter-county involvement that began as a Clare minor hurler in 1987. He spent two more years as a minor before graduating to the senior squad where he remained until 2007.
Midway through the 2008 season Fitzgerald, by then retired from playing, was appointed Waterford manager when Justin McCarthy stepped down after a heavy Munster SHC defeat to Clare.
Waterford reached an All-Ireland final and were beaten heavily again, this time by Kilkenny and while they did win their last Munster title under Fitzgerald in 2010, he was gone at the end of 2011.
In 2012 he began a five-year spell in charge of his native Clare, during which time they won an All-Ireland title in 2013 and a league in 2016.
But he moved on again, quickly taking up the management role in Wexford with whom he landed a first Leinster title in 15 years in 2019. Another five-year term came to an end there and this year he has spent time as coach to the Cork camogie team, which lost last Sunday's All-Ireland final to Kilkenny.
Meanwhile, Offaly GAA has confirmed the appointment of Liam Kearns as football manager for a three-year-term, subject to county board ratification.
The county's management committee has approved the recommendation of the former Limerick, Laois and Tipperary manager to replace John Maughan.
Chairman Michael Duignan, secretary Colm Cummins, treasurer Dervill Dolan, Stephen Darby and Paul Rouse, a former temporary manager himself, put forward Kearns' name.
He brings a wealth of experience to the position as Offaly seek to get back up to Division 2. Kearns was four years as Tipperary manager between 2016 and 2019, making an All-Ireland semi-final in his first year.