So when street designers came up with the concept of shared surfaces between pedestrians and traffic - cars and people separated only by painted lines or different coloured tarmac - Guide Dogs realised there would be problems. "Take away the kerb and blind people don't know if they are on the pavement or in the road," says Guide Dogs' consultant Peter Barker.
The charity began opposing the idea of shared surfaces, where the safety of visually impaired people isn't taken into account. But in negotiations with local authorities and designers it was claimed that the problems faced by blind people had already been solved in Holland, where the development of shared surfaces had been pioneered. So the association decided to ask the Netherlands Federation of Blind People about its experiences.
The federation reported that, contrary to what Guide Dogs had been told, blind people had not been consulted about the introduction of shared surfaces - they had protested, but had been ignored. So the two organisations began an international collaboration.
Two focus groups were organised. The first asked blind and partially sighted people from different parts of Holland about their difficulties with shared surfaces. The second was with the Dutch Ministry of Transport.
The architect responsible admitted he had made a mistake in not consulting with pedestrians, and promised to do so.
According to Barker, the collaboration with the Dutch federation was a partnership that benefited both sides. "It helped us and the Dutch," he says. "It raised the profile of the issue in Holland and it helped us to say to those who were advocating this system: 'You say this works in Holland, but where's your evidence? Our evidence is that it's a problem.' It's also given us some ideas on how to carry out research into design and make recommendations on how shared surfaces could be improved."
Baker also attributes the genesis of the partnership to a personal relationship with the chairman of the Dutch federation. "He's visually impaired and I'm blind, so we have a common appreciation of the problem," he says.
"Once it realised that we had a little bit of muscle to tackle the issue, the federation was only too pleased to get involved - it did a lot of the work locally in organising things, and we met the costs. It was a genuine partnership and we both played our part in the operation, using our respective competences."
Guide Dogs is now expanding its international partnerships and talking to a blindness organisation in Denmark, where blind people are experiencing the same problems.