Objective: To examine the effects of telephone prompting on attendance for the start of treatment and retention in treatment in a specialist alcohol clinic. Method: The study setting was a specialist alcohol treatment clinic. Participants were 172 clients attending as out-patients. An ABABAB design was used with planned alternating conditions, respectively, with or without a telephone prompt the day before the client was due to attend, over a succession of six consecutive 4-week periods. Results: Clients who were prompted were more likely to start treatment and attend further treatment sessions than clients who were not prompted. Conclusions: Telephone prompting is a simple and effective way to improve attendance for the start of treatment and retention in alcohol treatment.