The green light has been given for the demolition of Apollo House and Hawkins House as part of a €50m development for Dublin city centre.
An Bord Pleanala granted planning permission for the demolition of the two buildings and redevelopment of the plots in spite of opposition.
A management firm representing the nearby 66 Corn Exchange apartments and developer Balark Investments, which owns the Screen Cinema and College House buildings, both objected.
Over last Christmas and New Years, the focus on the homeless crisis centred on Apollo House after it was occupied by housing activists in a "direct action" move supported by a number of celebrities including singer Glen Hansard and movie director Jim Sheridan.
Now the Nama-appointed receiver to Cuprum Properties Ltd, Mazars, will demolish Apollo House and redevelop the 1960s office block. It is to be replaced by an 11-storey commercial office building.
The Office of Public Works (OPW) is the applicant for the redevelopment of the adjacent Hawkins House, which has long been regarded as one of the capital's ugliest buildings.
The appeals board decision will remove it from the Dublin skyline, replacing it with a new 10-storey building.
The joint plan to build a new office quarter, along with shops, restaurants, a public plaza and a new diagonal pedestrian street, will be one of the largest redevelopment projects in the city centre in recent times.
In giving the projects the go-ahead, An Bord Pleanala stated that Hawkins House is one of three "key" sites within the area of the Georges Quay Local Area Plan, which envisages the construction of a "mid-town" area of Dublin.
In their objection against the redevelopment of Apollo House, the Corn Exchange residents stated the new block does not represent a worthy replacement to the existing building.
In response, Cuprum reduced the proposed building's height by removing one storey, taking it down 13ft to 146ft tall.
Balark also objected, stating that the three "key" sites - their own land, Hawkins House and Apollo House - should be redeveloped together.
It said the piecemeal approach to the redevelopment has resulted in a number of inefficiencies and challenges.