Sixteen cases of the anterior choroidal artery syndrome are reported. In its completed form, this rare syndrome combines the triad of hemiplegia, hemianaesthesia, and homonymous hemianopia. CT examination confirms the diagnosis by revealing an area of reduced density situated in the posterior limb of the internal capsule, sparing the thalamus medially and encroaching upon the tip of the globus pallidus laterally, and corresponding to the distribution of the anterior choroidal artery. Incomplete forms of the syndrome are more frequent. Left-sided spatial neglect may accompany right-sided lesions, as may slight disorders of speech in left-sided lesions. Clinical-anatomical correlations are discussed.