OBJECTIVE: This study investigated prevalence, types and predictors of professional service use in families of children identified with attention deficit hyperactivity disorder (ADHD) in the community. DESIGN: SETTING: children with ADHD were identified through 43 schools using parent and teacher screening questionnaires (Conners 3 ADHD Index) followed by case confirmation using the Diagnostic Interview Schedule for Children Version IV. Parents completed a survey about professional service use in the last 12 months. MAIN OUTCOME MEASURES: data on variables potentially associated with service use were collected from parents (interview and questionnaires), teachers (questionnaires) and children (direct assessment). Logistic regression was used to examine predictors of service use in univariate and multivariable analyses. RESULTS: The sample comprised 179 children aged 6-8 years with ADHD. Over one-third (37%) had not received professional services in the last 12 months. The strongest predictors of service use were older child age (adjusted OR=3.0, 95% CI 1.0 to 8.9, p=0.05), and the degree to which the child's behaviour impacted on the family (adjusted OR=2.0, 95% CI 1.3 to 3.3, p=0.007), after controlling for ADHD subtype and severity, externalising comorbidities, academic achievement and parent-reported impairment. CONCLUSIONS: A substantial proportion of children with ADHD are not accessing professional services. Our findings suggest that the child's age and the impact of the child's behaviour on the family are the strongest predictors of service use. Given the demonstrated benefits from various interventions in ADHD, there is a need to improve case identification and referral for services.