Mr Demarco, one of the country’s most prominent advocates for contemporary art, will speak at a conference at Marchmont House this weekend.
The Edinburgh-born artist will tell gathered auctioneers, dealers, collectors and enthusiasts visual arts are “under-celebrated” in Scotland.
The Exploring Modern Scottish Sculpture event has been organised at the 18th century Borders mansion to celebrate UK modern sculpture.
Speaking ahead of the conference, Mr Demarco said: “Scottish sculpture has been under-celebrated even though the country has been home to some highly important sculptors.
“The task facing out art world is daunting when I compare Scotland to Italy where, in the heart of the Tuscan hills, is the incomparable collection created by Giuliano Gori in what is known as La Fattoria di Celle.”
Mr Demarco – who co-founded the Traverse Theatre in Edinburgh in 1963 – called on Scottish politicians to reconsider the role of sculpture in society.
He referred to art theorist Joseph Beuys’ idea of “social sculpture” playing a part in shaping society.
On Saturday, Mr Demarco will tell the conference that politicians need to be bold in celebrating artists to inspire new generations and put art back at the heart of daily life.
He added that the collection of modern work on display at the venue represents a beacon of hope for Scotland’s cultural future.
The event is the second in a year-long series promoting Scotland’s arts and crafts organised by Marchmont House and Lyon & Turnbull fine art auctioneers.
Marchmont’s director, Hugo Burge, said: “It is an honour to have Richard Demarco return to Marchmont, where he previously worked with the McEwen family to support Scottish arts – to build on the creative DNA the house has had and to look to the future.
“I’m excited we will be hosting a magical collection of artists, experts and enthusiasts to celebrate the subject of modern Scottish sculpture, celebrate hidden stories and celebrate a purposeful future for the role of art in Scotland.”
The tour of the sculpture at Marchmont House this weekend will include work by William Turnbull, Eduardo Paolozzi and Tim Stead, as well as local artists Charlie Poulsen, Keith McCarter and Frippy Jameson.
Philip Smith, the associate director of Lyon & Turnbull, added: “Marchmont is the perfect location to host a forum, the presentation of such a wonderful contemporary sculpture collection in a historic Scottish setting will make for a truly unique event.
Tickets for the event are available online from £55.
Visit eventbrite.co.uk for more information.