Background: If nurses have the communication skills and the time, they can play an important role in increasing the intrinsic motivation of patients with coronary artery disease (CAD) to change their lifestyle. Motivational Interviewing (Mo-Int) can be used to further support this role. However, few nurses are sufficiently proficient in applying Mo-Int skills. Increasing these complex communication skills may contribute significantly to achieve lifestyle changes in CAD patients. Aims: The aim of this study was to evaluate the coaching of nurses to skilfully use Mo-Int in a secondary prevention programme for CAD patients. Methods: The design was a before–after study of a learning strategy as a follow-up on a short Mo-Int workshop. At (on average) four-monthly intervals, the nurses received, three times, feedback and coaching by telephone and email on their use of Mo-Int skills in audio-recorded conversations on lifestyle change with CAD patients. The Mo-Int consistency of the nurses’ communication skills was scored using the Motivational Interviewing Target Scheme 2.1 (range 0–32). Results: Of the 24 nurses, 13 completed all audio recordings. The mean change in Mo-Int consistency of these completers between the first and the last audio recording was 6.4 (95% confidence interval 3.2 to 9.5). This change indicates an improvement from ‘a small part of Motivational Interviewing practice’ to ‘a mainly sufficient degree of Motivational Interviewing practice’. Conclusion: A one-year follow-up on a Mo-Int workshop with feedback and coaching improves Mo-Int skills of nurses. Healthcare professionals should be aware of the importance of a follow-up on training in complex communication skills, to develop and preserve competency.