THE BROADER PICTURE / A hard day at the office block

ALAIN ROBERT'S obsession with buildings began when he was 13 years old. Locked out of his parents' flat in Valence, in southern France, he shinned up eight floors and climbed in through a window. "It felt incredible. I was hooked and instantly wan ted totry something higher."

At first, his enthusiasm developed along predictable lines. He began to climb mountains. Later, he became a professional mountaineer, specialising in "free solo" climbing - that is, without ropes or other equipment. Now, at 32, he is a celebrity in Europe simply on account of his conventional climbing achievements; some consider him France's leading mountaineer. Recently, however, he has grown bored of mountains and returned to his first love: buildings.

High-rise office buildings are his preference, especially if they have lots of glass. "They look so fantastic. When I see one, I want to climb. It's hard to think of anything else." This is just as well. The risks do not bear thinking about, as Robert should know. He has been operated on 14 times as a result of various climbing accidents and claims to have more metal joints in him than the Eiffel Tower. On one occasion he survived a fall of some 20 metres. "Sometimes I feel more like a robot than a huma n being," he says.

In France, where he achieved his first urban triumphs, he is known as Spiderman. He has conquered buildings of anything up to 260m in height, many smooth and featureless. His secret is to twist his fingers (bound with tape for protection) and his feet inside the tiny cracks between each pane of glass. Such cracks are often no more than 2cm wide. He removes and replaces one hand or foot at a time, as he inches his way up the flat, vertical surfaces.

The search for bigger challenges - and particularly for buildings whose outer surfaces are made entirely of glass - has begun to dominate his life. "I'm addicted to them. I love looking at the reflections while I'm climbing. They're beautiful." Also, of course, there are the looks of amazement on the faces of office workers as he crawls past their windows. "They think I'm completely crazy," he laughs. "My dream," he continues, "is to find glass buildings all round the world - in Tokyo, San Francisco, Johannesburg, Sydney..." So far, the major obstacle to the realisation of this dream has been the law. He has been arrested three times since July. The first time was in Chicago, where he spent 12 hours in jail after scaling 40 of the 50 storeys of the Cit ibank building. Two months later, he was apprehended by gendarmes after climbing a building in La Defense in Paris, although he was released without charge. Then, in October, he travelled to New York.

At first, he felt spoilt for choice. "I spent my whole time walking around with my head craned upwards, dreaming of which one to climb next." Then he spotted his ultimate urban fantasy: 48 storeys of smoked glass and smooth chrome at 101 Park Avenue. Robert likes to compare the buildings he climbs to beautiful girls; this one, he says, was the Claudia Schiffer of skyscrapers. Within a few hours he had summoned a photographer and film crew and had begun to climb. The 200m ascent took less than 20 minutes. Shortly afterwards, while the office workers inside were still applauding him, he was arrested.

After a day in jail, he was released on bail - on condition that he did not climb anything in New York for two years. The frustration has been almost too much to bear. "I'm very unhappy. I've just seen a beautiful, black skyscraper on Seventh Avenue, andI know I'll never get near it." He is due to appear in court next month, charged with trespass and dangerous behaviour - one concern is that he might kill pedestrians if he fell on top of them. But these setbacks have not discouraged him: he is already planning other ascents, in France and other countries.

Although he has a wife and two children, he seems cheerfully indifferent to the dangers of his hobby. "It's my life, and I like to play with it. Risks make everything more real, more extreme. Everyone must die one day - maybe I'll die next week, or the following year. That's why what I do is so exciting - I can never say what's going to happen."