Mitochondrial disease presents with a wide, diverse spectrum of clinical manifestations at any age, often characterized by multisystem dysfunction. Movement disorders are a frequent manifestation, and may include ataxia, parkinsonism, myoclonus, dystonia, chorea, tremor. The phenotype of mitochondrial disorders, including the spectrum of movement disorders, may be very variable, even in patients carrying the same genetic mutation. Mitochondrial dysfunction may also play an important role in sporadic neurodegenerative diseases with movement disorders. Identification of a genetic mitochondrial movement disorder is challenging, but has been facilitated by new technologies, such as next-generation sequencing, thus identifying causative genes and eventually expanding the phenotype spectrum in the case of nuclear mitochondrial mutations. Identification of the underlying genetic basis of a mitochondrial movement disorder is crucial for patient management, as potentially mitochondriotoxic agents should be avoided and special precautions taken with anesthesia. This chapter gives a comprehensive overview of the spectrum of movement disorders associated with mitochondrial disease.