The present study compared the efficacy of a group-based cognitive-behavioural treatment (GCBT) delivered exclusively to parents of young anxious children (between 4 and 8 years of age) with the same intervention delivered to both children and parents, relative to a Wait-list Control condition. Parents of children in the Parent Only condition (N = 25) received 10 weekly sessions of GCBT whereas children and parents in the Parent + Child condition (N = 24) each received 10 weekly sessions of GCBT. Intent-to-treat analyses indicated that both active treatment conditions were superior to the Wait-list condition (N = 11), with 55.3% of children in the Parent Only condition and 54.8% of children in the Parent + Child condition no longer meeting criteria for their principal diagnosis at post-treatment. These treatment gains were maintained in both treatment conditions at six-month and 12-month follow-up assessments. There were no significant differences between the two active conditions on other outcome measures including parental psychopathology and parenting style. However, an unexpected finding was that parenting satisfaction and to some extent parenting competence reduced significantly from pre- to post-treatment regardless of the active treatment condition. The present results suggest that GCBT delivered exclusively to parents of young anxious children may be a viable treatment alternative for improving accessibility to efficacious treatments for children with anxiety disorders and for reducing costs associated with mental health care delivery.