Speaking after his firm won the President's Award at the Landscape Institute Awards on 27 November for its work on the Swansea Bay Tidal Lagoon, an ambitious project that harnesses tidal power to generate renewable electricity, Mattinson said the project was successful because landscape architects were involved from the start - a "significant difference".
"It's no longer the domain of the landscape architect to simply design and produce a beautiful public realm or a worthy report," he said. "I think that if we are going to flourish we have to lead from the front and we have got to change how the profession is received amongst fellow co-consultants and clients.
"We need to have the agreed script set out between all the parties including the client well ahead of the delivery process."
Mattinson pointed out that the profession has gone through some difficult problems over recent years in terms of the recession and a dearth of required skill sets, so despite the awards being a day of celebration the profession still needs to take stock and better educate clients as to all that landscape architects can do.
Mattinson, who is currently leading LDA's redevelopment work at Battersea Power Station and co-led the masterplan, detailed design and implementation of the London 2012 Olympic parklands, said it was "fabulous to be awarded by your peers - a fantastic achievement".
He added: "For LDA Design, doors have opened following our work on the 2012 Olympics. These doors can easily close and we have to seize the day and build on that fantastic opportunity we've been given. It isn't easy. It is a strong landscape-led approach that sets the practice apart and our ability to take a project from vision through to creative delivery."
"When we (landscape architects) are acting just as one of the parts in isolation, we are not acting as well as we can be."