This study examined the efficacy of a brief 2-h discussion group for parents of preschool children that show disruptive behavior on shopping trips. Forty-six parents with children aged 2–6 years were randomly assigned to either the intervention condition or a waitlist control group. Significant intervention effects were found for measures of problem child behavior, dysfunctional parenting styles and parents’ confidence in the parenting role. No group differences were found for parental adjustment or conflict over parenting. Intervention gains were maintained at 6-month follow-up. Results are discussed within a primary care and public health framework.