What Sweden also has, running in parallel with the state system, is a private school system.

FORBES: Egalia: Gender Neutral Schooling and School Voucher Programs

An Airbus has seven computer systems running in parallel, so as to provide enough redundancy to cope with computer breakdowns.

ECONOMIST: Drive by wire

Running in parallel with the will-she, won't-she of Mrs Fisher's impending delivery was the seemingly perennial question of when was a Briton going to win the Open again.

BBC: Age no barrier for Watson

While Japan and South Korea are co-operating over travel, security and other arrangements, this still looks like two World Cups running in parallel, rather than a unified tournament.

BBC: World Cup's uneasy team-mates

Running in parallel with the trials of love is an account of the earliest vibrators, as developed for therapeutic purposes by our hero, the irony being that, without realizing it, he is, like Charlotte, in the business of female liberation.

NEWYORKER: Hysteria

And with financial systems generally being susceptible to contagions, there may be something to be said for having numerous financial systems running parallel to each other rather than putting all our eggs in one basket.

ECONOMIST: A reader debate on Islamic finance