A right-handed 48-year-old female had clustered groups of seizures characterized by speech disturbance (attacks of verbal repetition and speech arrest) over a period of 7 years. Later, speech arrest was accompanied by perioral focal seizures. Magnetic resonance imaging and surgery found a low grade astrocytoma, centered in the left supplementary motor area. Postoperatively, no seizures or speech disturbances occurred for 3 years. This case confirms the main function of the supplementary motor area of the dominant hemisphere is connected with the initiation of speech and the setting into motion of the mechanism of speech.