Chip and PIN is a credit security system which consists of an embedded microchip in a credit or debit card for payment authentication; while it's had a hard time catching on in the United States, where magnetic stripes on cards remain the norm, chip and PIN is a major presence in the UK and Europe, and it recently gained a major toehold in Canada with Visa's adoption of the system.
While chip and PIN is meant to correct security weaknesses inherent in the magnetic stripe system, it has flaws. A Cambridge computer science graduate student named Omar Choudary documented several of these flaws in an MPhil thesis and suggested improvements to the system. The response of the UK Cards Association, which describes itself as "the leading trade association for the cards industry in the UK": Asking Cambridge to censor Choudary's work on the grounds that it "breaches the boundary of responsible disclosure." In the words of the Cards Association, "Our key concern … is that this type of research was ever considered suitable for publication by the University. It gives us cause to worry that future research, which may potentially be more damaging, may also be published in this level of detail."
Cambridge professor and security theorist Ross Anderson didn't see it that way: In a withering letter back to the trade group, he defended the publication of the thesis, saying that "Cambridge is the University of Erasmus, of Newton, and of Darwin; censoring writings that offend the powerful is offensive to our deepest values."