[4][5] In an open letter to the Irish Times in 1957 Desmond Guinness lamented the lapsing of the older Georgian Society and asked whether anyone would object to him restarting it.

[13] The society is a membership organisation of about 2,000 members whose purpose is to promote awareness and the protection of Ireland's architectural heritage and decorative arts.

In a major change, in 2008 a new entity called the Irish Georgian Foundation was given charge of the financial and charitable aspects, leaving the IGS as an unincorporated membership body.

The boards of both were merged in 2013 for reasons of governance, and the IGF is now the operating legal entity, while the IGS name and logo are retained for emotive purposes, and IGS members support the work of the IGF but have no formal role in its governance or property ownership; they do have a limited role in choosing a nominal head.

Another major project, which started in 2008, was the restoration of Dublin's 1760s City Assembly House in South William Street, the first purpose-built public exhibition gallery in Britain or Ireland.

The society runs a range of events, educational, exploratory, instructional (for example for property owners), some for members, some open.