Most students are happy to work hard, try their best and accept the consequences. But there are a host of commercial essay writers who are prepared to help those who can't be bothered. Universities have responded to the threat by trying to change the way they assess students. Increasingly students are being asked to orally present their work in front of a seminar group, or to answer questions from lecturers.

Up to 100,000 students a year now use dozens of shady companies to produce bespoke pieces of work guaranteed to secure high marks.

More and more students are plagiarising material - and buying essays online. According to one of several companies that trade in "off-the-peg" and custom-written academic work, they sell between 500 and 1,000 essays a week, mainly to overseas students studying in the UK. Prices start at £50.