Purpose: The aims of this study were to evaluate the efficacy of telehealth delivery of the Lidcombe Program of Early Stuttering Intervention, compared with a control group, and to determine the number of children who could be regarded as "responders." Method: A speech-language pathologist provided telehealth delivery of the Lidcombe Program during telephone consultations with parents in their homes, remote from the clinic. The study design was an open plan, parallel group, randomized controlled trial with blinded outcome assessment. Children in the no-treatment control group who were still stuttering after 9 months then received the same treatment. The primary outcome measure was frequency of stuttering, gathered from audiotape recordings of participants' conversational speech in everyday, non-treatment situations, before and after treatment. Results: Analysis of covariance showed a 73% decrease in frequency of stuttering at 9 months after randomization in the treatment group, as compared with the control group (95% confidence interval = 25%-90%, p = .02). Measures of treat-ment time showed that telehealth delivery of the Lidcombe Program requires around 3 times more resources than standard presentation. Conclusions: Telehealth delivery of the Lidcombe Program is an efficacious treatment for preschool children who cannot receive the standard, clinic-based Lidcombe Program. Avenues for improving efficiency are considered.