He is widely credited as having been instrumental in laying the original foundations of London Irish's most successful years, taking the club to third place in the Premiership, the final of the Amlin Challenge Cup and a Heineken Cup semi-final against Toulouse. After his departure, Booth became Head Coach and he continued to steer the Exiles through their most successful period of the professional era, leading the club to a Premiership Final and Heineken Cup tournament qualifications for three successive years.
Andy Martin, London Irish CEO said: "We have made great strides over the past couple of years to make this club successful both on and off the field by building a team which has a good mix of experience and raw talent. We are delighted therefore that Brian will be returning. He is a top class manager with a proven track record of success both at club and international level. We believe that his experience will help to strengthen our current resources and will be the boost we need to get back on track this season and beyond.
"There is no doubt that it has been a tough few weeks, something that we are all feeling. We would like to thank our supporters most sincerely for sticking with us and hope they will see that we are committed to making positive changes towards future success."
Smith said: "I am delighted to be returning to London Irish. Toby and I have always had a great relationship and that brought with it a lot of success on field in my time at the club and I know that we're destined for even greater things. We're building a new squad with fantastic potential and if we all pull together we can really make things happen."
Prior to England and London Irish, Brian was Defence Coach at Bath Rugby helping the club to reach the 2002/03 final of the Amlin Challenge Cup and the 2003/04 Guinness Premiership final. His coaching career had started with Sydney-based Eastern Suburbs who went undefeated in 2000 which led to a coaching role with the ACT Brumbies and a Super 12 final in 2001.
He is a dual rugby international having played at fly-half for both Australia (six caps) and Ireland (nine caps). He is also an Oxford Blue. He debuted for the Wallabies on their successful 1986 Bledisloe Cup Tour and played in the inaugural Rugby World Cup in 1987.