uddersfield may seem a long way from Ouagadogou, capital of the tiny West African country of Burkina Faso. For Cambridge-educated design engineer Sarah Hindle, 26, however, there is a powerful connection: water.

Sarah works for Arup, the global design engineering and business consulting firm, which helped design glossy projects such as the iconic Gherkin building in central London and the Millennium Bridge. In comparison to these architectural showstoppers, her current placement, working out ways to treat waste water in Huddersfield, may sound uninspiring. But Sarah disagrees.

Last year, she visited Burkina Faso to look at village water systems. She says the experience taught her that cutting-edge design doesn't need to be high-tech - it just has to work. "They had a new rope pump for their village well, made from old car tyres, which had a concrete cover on top to protect the water from contamination. You just had to turn a wheel and the water would be pulled up easily. They're easy to maintain but they make a real difference to people's lives."

While in Burkina Faso, Sarah met a local young woman who had lost her baby because she hadn't had access to clean water. It was a moving experience. "We were the same age, but our lives were so different. As an engineer, you're not helpless. You feel like you can design something that could make things better."

Arup spokesperson Anna Davidson says there's a move among large design-engineering firms towards this kind of pro bono work. "It provides stimulation to people within the company, and it means that we can offer our expertise."

Back in Huddersfield, Sarah says the trip tied in with a key part of her job as an engineer - talking to people to find out what they really need. "Every day, I spend a lot of time talking to people who work in the water system, looking at designs and drawings, and writing reports. You've got to understand the context - which pump leaks, which machinery is getting old."

Of course, there are different ways in which design engineering can be useful. Imagine a pedometer dog collar that lets you know how much exercise your overweight pooch needs. Dog-owners who are worried that Fido has been snoozing on the sofa while they've been in the office, would be able to check the number of steps their chubby canine had taken that day, and take him for an extra lap around the park if necessary.

Sounds far out? It's just one of the cutting-edge designs created by ingenious students on the two-year masters course in industrial design engineering that is run jointly by the Royal College of Art and Imperial College London. With its strong business links, the course provides a path into a career in design engineering. The field is certainly not the preserve of the solitary, basement-bound egg-head, says Professor Tom Barker, who runs the course. "The Wallace and Gromit image is not the case any more. Engineering is changing fast. We're not just inventing things - in a global economy, we need to take into account the marketplace and generate products and services that people actually want." Design engineers should be business-savvy as well as creative and technically adept, says Barker - and he should know. The youngest RCA professor on record when he got the job aged 38, Barker helped design the London Eye and his contacts book bristles with industry bigwigs.

The students earn their stripes working on corporate projects - like a robotic lighting system where spotlights can scoot along the ceiling to follow your movements around the room, change colour according to your mood, or turn themselves on and off. Last year, students designed new types of ice cream for Unilever and new furniture for B&Q, as well aspromotional installations for Sony Playstation.

Then there are the entrepreneurial designs, like the "Eglu", a high-tech, eco-friendly chicken coop made of curvaceous plastic, which has been a runaway success since the idea was hatched by four Royal College of Art graduates a couple of years ago.

"We promote sustainable design from a commercial point of view now," says Professor Barker. "Consumers are so aware of ethical issues, that it makes sense for companies too." He points to the "Concrete Canvas", a portable shelter that can be used in refugee camps or emergency situations. Once filled with water and inflated, the bag of concrete and textiles transforms into a sturdy structure where people can shelter.

Designed by two young RCA students, Peter Brewin and Will Crawford, it won the Saatchi and Saatchi Award for World Changing Ideas in 2005, and bears out Sarah Hindle's point - that design engineering will never be a career "where you sit at a desk all day."