Background: Effective communication between clinicians is essential for safe, efficient healthcare. We undertook a study to determine the longer-term effectiveness of an education session employing a structured method to teach referral-making skills to medical students. Methods: All final year medical students received a forty-five minute education intervention consisting: discussion of effective telephone referrals; video viewing and critique; explanation, demonstration and practice using ISBAR; provision of a memory aid for use in their clinical work. Audio recordings were taken during a subsequent standardised simulation scenario and blindly assessed using a validated scoring system. Recordings were taken immediately before (control), several hours after (intervention), and at approximately six months after the education. Retention of the acronym and self-reports of transfer to the clinical environment were measured with a questionnaire at eight months. ResultsReferral clarity at six months was significantly improved from pre-intervention, and referral content showed a trend towards improvement. Both measures were lower than the immediate post-education test. The ISBAR acronym was remembered by 59.4 (n?=?95/160) and used by the vast majority of the respondents who had made a clinical telephone referral (n?=?135/143; 94.4 ). ConclusionsA brief education session improved telephone communication in a simulated environment above baseline for over six months, achieved functional retention of the acronym over a seven to eight month period and resulted in self reports of transfer of the learning into practice.