It’s a measure of Robert Redford’s enduring appeal, even at the grand age of 70, that when he says, “I’m all yours”, just for a fraction of a second, a tiny bit of you wishes it were true. In truth, despite an occasional dimpled grin – when you catch a flicker of the old Redford screen charisma that made your 13-year-old heart pound in Butch Cassidy and the Sundance Kid – and surprisingly gentle manners, he has neither the playfulness nor the hint of danger of the natural-born flirt.

This should be music to his ears, if Redford is to be believed, since the poor man has spent decades trying to be taken seriously, only to have his good looks stand in the way. When he appeared on the scene, journalists of both sexes drooled. A Newsweek profile by a male writer is a classic of the type, launching into his “gorgeousness” thus: “The head is classically shaped, the features chiseled to an all-American handsomeness, the body athletically muscled…” Not to be outdone by this homo-erotic rhapsody, the women writers swooned: “He gives you the feeling that even his sweat would smell good”, and raved about his “cool” and “sexual arrogance that is far more fetching than any amount of sweet talk”.

What is more interesting, apart from the quaint gush of these early pieces, is to see how consistent Redford has been from his earliest interviews in the Sixties and Seventies about the issues that he is known for now: anti-Hollywood, pro-environment, concerned about youth apathy, questioning of the government and sceptical about politicians in general, as well as the power of corporations. He has always been protective of his privacy and had periods of withdrawal from work – even at the height of his fame – to travel around Europe or do his own thing.

Way back in 1970, a year after he shot to fame as the Sundance Kid, Redford vented his frustration about Hollywood to a young Derek Malcolm: “You can’t run an art form like a business any more and they’re still trying to. Films to them are just like vacuum cleaners or refrigerators. The approach sickens me.”

Not content to bitch from the sidelines, Redford founded the non-profit-making Sundance Institute in 1981 – using his own land and property in Utah – to support emerging screenwriters, directors, composers and producers who work alongside established names to craft their skills and develop their projects. To this was added the now internationally famous Sundance Film Festival which, to its creator’s evident discomfort, has become so successful it has assumed the mantle of the Cannes of America, with all the trashy commercialism that entails.

This is anathema to Redford, whose rueful complaint to me is: “What happened was the success of it brought the media, and then the merchants came and the stars came… Look, when Paris Hilton comes to the festival, she’s coming to the parties. We’re doing the same that we always have, but then the brand names come to take advantage of the festival and they throw parties to promote their brands and they say, ‘Come and we’ll give you a free coat or a free perfume or we’ll take your photo.’ I can’t control it because it’s a free country – that’s the reality and it is ironic. But I don’t worry about our mission as long as we stay true, and the Lab is non-profit and that’s the purest thing about Sundance.”

Naturally, with Sundance’s success, come the knockers. A counter-festival, Slamdance, established itself in Utah in the Nineties to show the films the organisers believe Redford has turned his back on – but there’s no evidence that his vision has been diluted. He may be attracted to the likes of The Horse Whisperer, which appeals to his romanticism about the American landscape he fights to protect, his love of horses and his sadness about the dying ranch culture of the West, but the films that have come through his “Lab” or have been showcased at the festival are very different and include Pulp Fiction, Sex, Lies and Videotape (the director, Steven Soderbergh, and Redford have since fallen out), Boys Don’t Cry, Orlando, The Blair Witch Project, Memento and Little Miss Sunshine.

Redford has worked equally hard on environmental issues, both publically and behind the scenes, and has a slew of awards in recognition of his contribution. The Utah home he built himself almost three decades ago was fitted with solar panels – visitors have commented on its rather spartan decor – long before it was fashionable to be green. He successfully campaigned against a huge power station being built between five national parks and disgruntled locals – Utah is a Republican stronghold – responded by burning an effigy of the star. Most unglamorously, he took on the role of the local sewerage commissioner with a mission to transform the area into an independent municipality with its own produce and energy resources.

For his pains – and even his detractors could hardly accuse the man of not backing up his words with action – Redford is hammered for being earnest or worthy, impatient, arrogant, humourless, a control freak and so on. One of the biggest and legitimate complaints against him is that he is always late. He once kept a Sunday Times journalist waiting seven hours, after she had made the epic trek to Sundance. Paul Newman, his co-star on Butch… and The Sting, presented him with a needlepoint runner stitched by Joanne Woodward (Mrs Newman) that read: “Punctuality is the courtesy of kings.”

This was a revealing rebuke since it suggests – something one can glean from the early cuts when the actor was a bit more forthcoming – that Redford’s early chippiness about being born on the wrong side of the tracks has prompted grandstanding posturising to demonstrate that he’s as important, if not more so, than the Hollywood royalty he had joined. Newman, who is a friend, was gently trying to point out that such behaviour is not classy.

I would have liked to have asked Redford about his punctuality problem, but our interview, of course, was cut short by his late arrival. However, I should add here, it was the star himself who dared to defy the publicity martinets by insisting that he make up the extra 15 minutes in his own lunch hour. This was gracious of him and also provoked an unexpected conspiratorial mirth between the interviewer and interviewee. “I’m here to serve,” he kept saying plaintively, and moaned that, “They have me jammed to the gills.”

Redford describes himself as coming from “a lower-working-class family. My dad was a milkman and supported us with no money. We didn’t have anything. I grew up in a Mexican neighbourhood [Santa Monica, 12 miles from Hollywood, known as “the home of the homeless”] where you had to provide your own entertainment. I was blessed that I was athletic and so could do sports.”

Explore Film

• Film Reviews

• Trailers

• DVD

• London Film Festival

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010