Acoustic data were collected twice pre‐treatment, once post‐treatment, and 6 months post‐treatment on three atypical Parkinson’s disease patients following intensive voice therapy. Using a custom‐built software program, the following variables were measured: maximum duration of sustained vowel phonation and sound pressure level from sustained vowel phonation, a standard passage, and spontaneous speech. Using the C‐Speech application [Milenkovic, J. Speech Hear. Res. 30, 529–538 (1987)], fundamental frequency variability was measured from a standard passage and spontaneous speech. Single‐word intelligibility was calculated using naive listeners’ perceptions. The patients achieved statistically significant improvement on all variables post‐treatment but did not maintain improvement as a group during reading and spontaneous speech by the 6‐month data collection session. These results suggest the effectiveness of intensive voice treatment in atypical Parkinson’s disease as well as provide insight into the und...