Purpose. This study was designed to compare expert consultant trainers and less experienced, in‐house trainers in providing basic training in motivational interviewing (MI) for juvenile corrections employees. Methods. Trainees (n= 1,552) attended a 3‐day workshop administered by either a member of the Motivational Interviewing Network of Trainers (MINT) or a corrections staff member who had been trained by a MINT trainer. Results. Pre‐ to post‐test MI knowledge and skill gains did not vary between MINT expert and internal trainers, and increased for both groups. MINT trainees were more motivated to learn MI and expected it to be more effective in their work compared with those trained by corrections staff. MINT trainers were perceived as more knowledgeable about the topic, whereas corrections staff trainers were rated as better at utilizing handouts and visual aids. The groups did not differ on other measures of trainee satisfaction. Conclusions. These data suggest that a train‐the‐trainers model, in which expert consultants provide initial trainings to develop a pool of staff to provide subsequent trainings, may be as effective as a model that relies exclusively on expert trainers.