Sixty patients with missile wounds confined to one of the four quadrants of the brain were investigated. All patients had neurosurgical verification of the limits of their lesions. The incidence and severity of constructional apraxia was studied using the WAIS Block Design and Object Assembly subtests, and the Bender Gestalt Test. A uniformly significant caudality effect was obtained with more posteriorly localized lesions resulting in more severe constructional apraxia. A significant laterality effect was obtained on two of three criterion measures with uniformly inferior performance by patients with right hemisphere lesions. The magnitude of the laterality effect, however, was less than that of the caudality effect for all criterion variables. The degree of severity of constructional apraxia in patients with right posterior lesions was uniformly greater than that of patients with other quadrant loci. The incidence of constructional apraxia in the four quadrants varied as expected with the left anterior lesion sample showing very little evidence of constructional apraxia, while the right posterior sample showed a high incidence of such deficits. The absolute incidence of significant constructional apraxia in all samples was suprisingly low. This finding might be partially accounted for by the age and general good health of the subjects studied, the relative absence of general cognitive impairment in the majority of subjects, and the discrete nature of the lesions.