England full-back Mike Brown is free from concussion symptoms but will not be rushed into contact training.
Harlequins star Brown joined up with England's mini training camp at their Bagshot base this week, for individually-tailored strength and conditioning work.
The 29-year-old has not played since suffering concussion after-effects following England's RBS 6 Nations victory over France on March 21.
Brown missed England's 19-9 defeat in Ireland after being knocked out during the 47-17 victory over Italy at Twickenham on February 14.
The 37-cap full-back joined the likes of Joe Marler, Ben Morgan and Jack Nowell in England's small meeting, for players from those clubs not involved in late end-of-season action.
England's first official World Cup training camp starts on June 22 and will start with gruelling conditioning and fitness work.
Head coach Stuart Lancaster has already pledged the training camp in Denver, Colorado next month will be "grim", as he bids to turn England into one of the fittest sides at the World Cup.
Brown is now technically free to take full part in any training, but could stand to benefit from the fact England do not have any full-tilt contact work slated in their immediate calendar.
The current thinking behind concussion recovery is that, after several incidents, players may stand to benefit from as much time without full contact as possible.
Brown's readiness for action is a clear World Cup boost for Lancaster, but England's medical team will also give the Southampton-born star the chance to ease his way back into proceedings.