 Meanwhile, in late 1963, Serong started to redeploy members of the team into combat advisory roles, and by February 1964 some officers and NCOs were working with Special Forces teams involved in counter-insurgency operations.Resulting in the first involvement of Australian personnel in combat during the conflict, this was a significant decision; it was retrospectively approved by Wilton, who lifted earlier restrictions on the role of AATTV personnel that had prevented them being involved in combat.According to his biographer Anne Blair, Serong believed in the need to prevent the spread of communism throughout South East Asia, conceiving his mission in South Vietnam in terms of the Domino Theory.