Just after 11am every workday, Bombay’s famous dabbawallas stream off the city’s railway network into the downtown business district to deliver hot, home-made meals to an army of hungry office workers.

Carrying tiffin boxes lovingly packed by wives and mothers in nearly 200,000 surburban kitchens, these 5,000 lunch delivery workers are part of one of the world’s most admired distribution systems.

Employing a complex colour-coded logistics process, the dabbawallas (can-carriers) complete a door-to-door service across 15 miles (25km) of public transport and 6 miles (10km) of road with multiple transfer points in a three-hour period.

In a system finely tuned over 120 years they maintain an error rate of only one in eight million and have drawn attention from leading business schools, including Stanford.

Now, the power of their unique system and loyal customer base is being harnessed by top multinationals.

Microsoft, the world’s largest software company, tapped their network last month to launch its new Vista operating system.

Wearing branded caps and T-shirts, the dabbawallas distributed leaflets with tiffin boxes offering discounted prices on laptops and PCs with a local dealer. Every sale earned a 100-rupee commission (£1.20). Microsoft India claimed the unique promotion as a success. “They have access to 200,000 households. It’s amazing,” Rishi Srivastava, client business director, said. “We more than achieved the marketing objective we set ourselves.”

Raghunath Medge, the president of the Bombay Tiffin Box Supply Charity Trust, which oversees the dabbawallas, is regularly asked to give management presentations. “Proper time management is our key to success. We do everything to keep the customer happy and they help in our marketing,” he said in a recent lecture. Most new customers are referred, and the service, which costs between 150 and 300 rupees a month, is growing by about 10 per cent a year. Fans include Sir Richard Branson, the Virgin boss, who joined their rounds in 2005 and the Prince of Wales, who invited two dabbawallas to his wedding to Camilla Parker Bowles after he met them during a 2003 visit.

Distinguishable by their trademark white Gandhi topis, they are descendants of the soldiers of Shivaji, the legendary 17th-century warrior king. The trade, which originates from British rule, is passed down through the generations, with village elders recommending new recruits. About 85 per cent are illiterate, making the fact they employ a ten-digit alphanumeric code to track deliveries — like shipping companies — all the more remarkable.

Knowledge of the system is held by mukadams, experienced dabbawallas, who oversee financially independent sub-groups of younger workers. Each group is competitive for new customers, although forbidden from undercutting each other, and co-operative for deliveries.

However, dabbawallas don’t see what the fuss is about. Vasant Bacche, 35, packing a cart outside Churchgate Station in Bombay, said: “I don’t know about management schools. I can’t read and write. That’s why I’ve done this for 15 years.”

Packed lunch

7am-9am Tiffins collected from homes

9am-11am Board trains, sort boxes at intermediary stations according to delivery area (single tiffin can change hands three to four times)

11am-12pm Arrive Bombay, fan out to loading points, more sorting and loading on to handcarts, bicycles and persons

12.30pm-1pm Deliveries

2pm Process moves into reverse

6pm Empty tiffins returned to homes

— Trust registered in 1968

— 35-40 tiffins per dabbawalla, each of 2kg

— Colour code denotes owner, work address and floor

— New dabbawalla’s minimum investment: two bicycles (4,000 rupees), wooden crate (500 rupees), white cotton kurta pyjama (600 rupees) and one Gandhi topi (20 rupees)

— A 20-member group has 675 customers and earns 100,000 rupees a month. Average individual monthly income 5,000-6,000 rupees minus 15 rupees contribution to the trust.

— There are only two female dabbawalas

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