Researchers estimate that 89% of people with Parkinson's disease (PD) have a speech or voice disorder including disorders of laryngeal, respiratory, and articulatory function. Despite the high incidence of speech and voice impairment, studies suggest that only 3-4% of people with PD receive speech treatment. The authors review the literature on the characteristics and features of speech and voice disorders in people with PD, the types of treatment techniques available, including medical, surgical, and behavioral therapies, and provide recommendations for the current efficacy of treatment interventions and directions of future research.