The 23 year-old winger, who passed through all levels of Swansea Schools, Swansea RFC and Wales age group rugby, left for Cardiff in 2003, signing a two-year contract. However, having been given limited first-team opportunities, as well as being laid low by injuries, the young star has been eager to return to his home region.
Ospreys' Rugby Manager, Derwyn Jones, says: "Johnny is one of Welsh rugby's hottest prospects and his skills are perfectly suited to the type of open and exciting rugby we play at The Ospreys. When you consider how his former teammates Jonathan Thomas and Richie Pugh have progressed with us in the last few years, it's the perfect place for him to fulfil his potential."
Ospreys' joint-MD, Mike Cuddy, adds: "Signing a player such as Johnny is great news for the region and demonstrates our commitment to developing young Welsh talent. We're extremely excited about working with him as he's a quality player with the potential to become an Ospreys regular and a full Welsh international.
"Furthermore, his arrival also raises the competition for places to new levels which is vital if we want to continue developing a squad of players to challenge the very best in Europe."
Vaughton said: "The Ospreys are quickly becoming one of the most feared sides in Europe and trying to break into a team packed with so many international stars will be a massive challenge. Nevertheless, I'm confident that I have the ability to succeed and can't wait to start working with the coaches and the rest of the team."
The annual Women's club launch was held at the Wales Centre of Excellence where National Women's Head Coach and Programme Lead Rhys Edwards, Competition Secretary Adrian Howell and Cardiff Met player Ffion Jones express eagerness for the new campaign to get under way.
WRU TV follows Wales' RWC training squad on day one of their camp in North Wales. The squad were greeted to an official welcome in Colwyn Bay and then headed for an afternoon of team building at ZipWorld