Speaking from Australia, Larkham said: "I am looking forward to coming to Edinburgh. I want to bring a winning culture to the team, and looking at some of the players already there such as Mike Blair and Chris Paterson, there is a lot of potential in the squad. Coming from Brumbies, I am used to being involved in the building of a successful team.
"One of the things that attracted me to Edinburgh is the team environment and the way in which my contract negotiations were carried out. The offer was not the highest as I shopped around a few clubs, but I found this was the best package for me and my young family. I love the city having been there a few times, and I am looking forward to making a difference when I arrive."
Edinburgh Rugby's Executive Chairman, Alex Carruthers added: "Stephen is truly a world class player and we are delighted he is joining us next season. He is undoubtedly one of the best fly halves in the game and we expect him to have a major impact at Edinburgh, not only with his influence on the field, but also in the dressing room given his experience at the highest level.
"We have said from the very beginning that we intend to build a squad of current Scotland internationalists, young local talent and world-class players, and with Stephen coming on board we have done that. We can now look forward to developing as a team and start realising our long-term ambitions to challenge the very best in Europe."