He took over the captain's role at Edinburgh at the start of the 2002-03 season before taking over as interim head coach from Frank Hadden in September 2005. During his time with the club, he captained Edinburgh to win the Bank of Scotland Pro Rugby Cup in 2003, the final of the Celtic Cup later that year and the quarter-final of the Heineken Cup in 2004.
Todd said: "Edinburgh has been a huge part of my life and I will always have a real emotional attachment to this beautiful city and more importantly to the club. The people I've played and worked with here feel like a part of my family and I've made some lifelong friends.
"I can see some great things happening here in Scotland and it's disappointing that I won't be part of that. For both the Edinburgh Gunners and Scottish Rugby, things are turning for the better and I have real belief in Gordon McKie [Chief Executive] and Frank Hadden [Scotland coach] to take rugby in Scotland forward in the right direction.
"I have seen some fantastic rugby played here by Edinburgh and we are as good a team as any in Europe. We also have a passionate group of fans who I will miss greatly. I have received countless letters and emails from them over the years and always enjoy a chat with them after matches at the stadium.
"The sponsors who have been involved with Edinburgh during my time here have also been superb for me and for the team, particularly our current main sponsor Magners. Until my post has been filled nothing will change here. The Gunners are a winning team and I'm fully committed to ensuring that continues," he concluded.
Scottish Rugby Chief Executive Gordon McKie said: "Todd has made a great contribution during his time here as a player and more recently as interim head coach. We will miss his undoubted experience, wide knowledge of the game and leadership qualities. He is a well respected individual across the whole organisation.
"We respect his decision to return to New Zealand sometime between now and the end of the season and thank him for his contribution and commitment to Scottish Rugby over the past five years. In the meantime, the recruitment process for Todd's successor will begin and further communication will follow on that in due course," he concluded.
National coach and former Gunners' coach Frank Hadden said: "There is no doubt that Todd has been the most influential overseas signing in Scottish Rugby. As a player, it was his error free consistency that really caught the eye, but it was his role as captain that was equally important to the development of Edinburgh Rugby. He gave us all a great insight into the standards required at the highest level in all aspects of professional rugby. In so doing, he instilled in the players the confidence that they could, with the right attitude, match these standards themselves.
"As a coach, he demonstrated a wisdom beyond his years, with a sharp eye for detail and a sound understanding of the bigger picture. His contribution to the game in this country cannot be underestimated and we wish him and his family all the best on his return home," he added.
The post for Edinburgh Gunners head coach will be advertised on the Scottish Rugby website (www.scottishrugby.org).