Prince William and Kate Middleton's relationship began as students in Scotland in 2001. The couple met at St Andrews University, Fife, on an art history course, although William later switched to geography.

The Royal family traditionally offers stage-managed photo calls in return for their privacy during their holiday but this broke down when paparazzi pursued Prince William and Miss Middleton at Klosters ski resort shortly before they graduated in 2005.

As interest in their relationship grew, Miss Middleton quickly became besieged by the media. Following the publication of a photo showing her on a London bus, her lawyers wrote to newspaper and magazine editors asking them to respect her privacy.

In 2006, Miss Middleton was a guest at Sandhurst, when the prince was commissioned as an officer in the British army. It was the first occasion that she had been seen at a high-profile public event also attended by the Queen and other senior royals.

It sparked a frenzy of speculation worldwide about an imminent engagement announcement. The former High Street store Woolworths even designed a range of memorabilia in anticipation of the event, including china plates, thimbles and mouse mats.

But the relationship was coming under strain as photographers followed Miss Middleton's every move. The couple broke up in April 2007, insisting they were "just good friends" after being pictured at the Princess Diana tribute concert three months later.

Before too long, the Prince and Kate Middleton were regularly spotted together.

And then Miss Middleton began reappearing at official engagements.

They could also be seen at a number of sporting events and are seen here watching England play Italy at Twickenham.

She was at his side as he was given his RAF wings by his father.

The prince has now qualified as an RAF search and rescue pilot and is co-pilot in a four-man rescue crew.

Kate, meanwhile, is forging a career as a photographer.

Their engagement was announced in a brief statement released by Clarence House and they will marry in London in spring or summer 2011.