Purpose: Ultrasound can provide images of the tongue during speech production. The present study set out to examine the potential utility of ultrasound in remediation of North American English /r/. Method: The participants were 2 Canadian English-speaking adolescents who had not yet acquired /r/. The study included an initial period without ultrasound and 13 treatment sessions, each 1 hr long, using ultrasound. Speech samples were recorded at screening and immediately before and after treatment. Samples were analyzed acoustically and with listener judgments. Ultrasound images were obtained before, during, and after the treatment period. Results: Three speech-language pathologists unfamiliar with the participants rated significantly more posttreatment tokens as accurate [r]s in single words and some phrases. Acoustic analyses showed an expected lowering of the third formant after treatment. A qualitative observation of posttreatment ultrasound images for accurate [r] tokens showed tongue shapes to be more similar to those of typical adults than had been observed before treatment. Participants needed continued practice of their newly acquired skills in sentences and conversation. Conclusion: Two-dimensional dynamic ultrasound appears to have potential utility for remediation of /r/ in speakers with residual /r/ impairment. Further research is needed with larger numbers of participants to establish the relative efficacy of ultrasound in treatment. (Contains 4 tables, 4 figures and 2 footnotes.)