The companies range from Xerox and Glaxo Wellcome to the local East Hertfordshire health authority.
"We don't do a specific thing with one particular company because we want to involve all our pupils. It's part of the curriculum thinking rather than an add-on extra," says headteacher Richard Foster.
He estimates that each pupil will undertake at least six different business-related activities during their time at the school.
Every year, 200 Year 11 pupils go on work experience and take part in interview practice with local businessmen.
Their counterparts in Years 7 and 8 have an industry activity day and Year 10 pupils go out of school for careers talks in business settings.
In addition, the school regularly takes part in competitions organised by its business partners. One recent example is when pupils designed a marketing strategy for a breakfast cereal with Cereal Partners UK, the maker of Shredded Wheat.
For some this may be a step too far. Surely the company is getting free market testing at the expense of pupils? But Mr Foster doesn't see it like that.
"You have to recognise the 'what's in it for us?' syndrome. Business involvement is still interpreted as a begging bowl opportunity by some people. But it has to be a win-win situation. It's not sustainable unless schools think of what businesses might gain from their involvement with them," he said.
Even then there can be problems. Marks amp; Spencer was heavily involved with the school as part of a project where pupils planned the opening of a new shop. Unfortunately, the link has lapsed while the company does it for real.
"Inevitably businesses have other priorities and concerns. You have to make projects robust so that you can continue them yourself if you have to," says deputy head John Walton.
Apart from a mentoring scheme for Years 10 and 11 and funding to cover a yearly teacher placement in industry, all the funding for business links comes from the school's existing budget or from the companies themselves.
That is something Mr Foster would like to see change. "It is relatively easy to link into major companies, but most employment is in small and medium enterprises.
"Finding ways to link into them is much more difficult. To do that we would need to receive funding for a permanent member of staff.
"Their job would then be to go out and spend time making the right connections and raising business awareness of what is happening in schools," he said.