Consultation is a key competency area for school psychologists, though much is unknown about how school psychologists develop the competency to consult. Deliberate practice (DP) is a promising approach to enhance use of communication skills, thereby supporting consultation competence. DP training included multiple opportunities for video-recorded consultation practice in response to a consultee's request for assistance, self-reflection on skill application, and corrective supervisory feedback. In this randomized controlled trial, 109 school psychology graduate students across 45 training programs received either consultation training as usual delivered through their first consultation course (control group; n = 61) or a supplemental DP training intervention in addition to their first consultation course (treatment group; n = 48). Students who completed the DP training significantly increased their use of communication skills during a simulated practice opportunity, while the control group participants did not. Students in the DP condition also reported significantly greater self-efficacy than students in the control group, although students in both groups reported significantly greater self-efficacy over time. DP participants also reported high levels of training satisfaction. Implications of these findings for the design and delivery of consultation training and supervision are discussed.