The grandson of designers Charles and Ray Eames is giving a lecture in Dublin next Tuesday to promote his grandparents' ideas about design, writes Emma Cullinan

We've all heard of Eames' chairs, but what made them so special and enduring? The grandson of design duo Charles and Ray (a woman) Eames has a deep understanding of their design methods and philosophy, and next week will explain them to an audience in Dublin.

Eames Demetrios, along with other members of his family, has taken charge of the Eames legacy to protect and publicise their furniture, house and films, and to promote ideas about design.

As part of this sharing of design awareness, he tours the world giving talks to architects and other designers. A designer's commitment to the client, and the creation of objects that are really useful, are high on the agenda.

Charles and Ray Eames met at the Cranbrook Academy of Art, Michigan in 1940. Charles was running the school's industrial design department with another legendary architect and furniture maker, Eero Saarinen: both would go on to be remembered as pioneers of organic furniture (which is shaped to fit the human form).

Their reputation was helped by winning an organic furniture competition sponsored by the Museum of Modern Art in 1941, and aiding the pair on the creation of the winning projects were students Ray Kaiser and Harry Bertoia (who later designed iconic wire mesh chairs, principally for Knoll).

Charles and Ray married in 1941 and created a studio in their apartment where they deepened their knowledge of moulded plywood furniture production by experimenting with sheets of ply and glue types, to create furniture of optimum shape and strength. Their design skills spread into graphics, filmmaking, set and house design (they designed their own home as part of the Case Study House project sponsored by Art and Architecture magazine).

As with most children of parents, or grandparents, who are well-known in a specialist area, it took Demetrios a while to realise just how famous his grandparents were: and, anyhow, their fame grew with him. "Charles and Ray are more famous now than they were when I was growing up. When I was a child about one in 10 people who heard my name would say 'Oh, any relation?' and a smaller proportion would get excited because they really knew what my grandparents were about."

For the young Demetrios, whose first name is Eames because his mother was an only child and his parents wanted him to carry on the family name, his grandparents were a joy to be with. "They were just great people who were fun to be around. Even as a child I knew they were very special and that their house was beautiful. Although I did grow up thinking that every child visited their grandparents at film festivals and saw cool films."

The filmmaking made an impression: it is now one of Demtrios' main occupations although, like his grandparents, he is involved in a number of activities, including art installations and carrying on his grandparents' legacy.

There is the Eames Office which, among other things, puts Eames films on DVD and works with furniture manufacturers on Charles and Ray's designs, and there is the Eames Foundation, which is restoring and protecting the Case Study House where Demtrios has an office.

The Eames family is keen on keeping the furniture design true to the original by working with licensed manufacturers (Herman Miller in America and Asia and Vitra in Europe).

There are inevitable changes as the world moves on, and these have included (in close consultation with the family) more eco-friendly glue to hold the plywood together and greener plastics for the moulded chair. On the Case Study House there are ongoing repairs to the structure which was made from off-the-peg materials.

"The house could just be described as a pair of steel boxes yet what is amazing is that it feels so comfortable in the landscape; more comfortable than many houses that try to blend into the landscape organically.

"It goes back to the honesty of materials and the importance of siting. Charles and Ray were going to cantilever the building over a meadow but then realised that they were making the classic mistake of taking a beautiful site and destroying it, which is something we've all seen done."

Continuing his grandparents' legacy was a sort of calling, says Demetrios who got to know his grandmother better when he moved to LA after leaving college and "hung out with her", (she outlived her husband by 10 years, dying in 1988).

"That's when I began to appreciate what they'd achieved. When Ray died I realised that there were a lot of things I knew about Charles and Ray that others didn't know and I wanted to help share them."

In next Tuesday's lecture, Demetrios will talk about the perennial nature of good design which he attributes to the likes of Mies van der Rohe and his own grandparents. "Charles and Ray didn't make a vintage chair, they made a chair for tomorrow. It wasn't something that was only valid in their lifetime. They created a system for giving the customer what they wanted."

In the Eames world this is known as the "guest/host" relationship. "And I can't wait to get to Ireland because I hear that you are great hosts," says Demetrios.

The Eames felt that the responsibility of an architect and designer is to address people's needs: the people are the guests of the designer.

This is design as a world-changing and problem-solving exercise: this notion of design over style resonates in today's world where certain prominent buildings are coming under attack for being more like sculptures than useful buildings.

Charles and Ray worked with models and not sketches (these came after the series of models had produced the final design), and tonight there will be slides showing Charles and Ray working on models, through to a completed piece of furniture. This evolution of an object works as speeded up vernacular design, says Demetrios. "It's a bit like what happens in real life where, through trial and error, people come to a mature point. No one person designed the shape of the spoon and fork, it just happened over time."

And once something has been perfected it should probably be left alone, says Demetrios. He tells the story of how his grandparents went to India in 1958 and saw the traditional Loca drinking vessel whose design had evolved over centuries (it's like a glass, made of brass, and pinched in at the top).

"Someone could make an addition to the Loca that people would acclaim as the most beautiful thing they'd ever seen, yet if it had no useful function, then the chances are that it would disappear over a couple of generations.

"But if someone added something that made it even more useful it would stay."

This really is design for humankind. "There's an overlap between the designer, client, community and society," says Demetrios. "If you can work in the area where they all overlap then you'll design something that you believe in and which helps the world."

The lecture takes place at 6.30pm next Tuesday, May 10th at St Michael and John's Church, Essex Street West, Temple Bar, Dublin 2. For more information contact vitra@projectoffice.ie.

An exhibition of furniture by Ray and Charles Eames will be held from Wednesday May 11th-28th (Monday-Saturday, 10am to 5pm) at the Project Office showrooms on the corner of Exchange Street Upper and Essex Street West, Temple Bar, Dublin 2. Admission is free. In association with the Vitra Design Museum, in Switzerland, the exhibition will comprise original pieces and prototypes from the 1950s and 1960s, along with Eames pieces currently in production