Purpose: This randomized controlled study investigated whether a supplemental treatment designed to teach triadic gaze (TG) as a signal of coordinated joint attention would yield a significantly greater increase in TG in the experimental versus control group. Method: Eighteen 10- to 24-month-old children with severe motor impairments were randomly assigned to an experimental (n = 9) or control group (n = 9). For approximately 29 sessions over 17 weeks, experimental participants received TG treatment twice weekly with a speech-language pathologist in addition to standard practice. Control participants received only standard practice from birth-to-three therapists. Coders who were masked to group assignment coded TG productions with an unfamiliar speech-language pathologist at baseline, every 3 weeks during the experimental phase, and at the final measurement session. Results: TG increased across groups from baseline to final measurement, with the experimental group showing slightly greater change. Performance trends were examined using experimental phase moving averages. Comparisons revealed significant differences between groups at 2 time points (at 12 weeks, r = 0.30, a medium effect, and at the end of the phase, r = 0.50, a large effect). Conclusion: The results suggest the promise of a short-term, focused treatment to teach TG as a behavioral manifestation of coordinated joint attention to children with severe physical disabilities.