In this article, methods for measuring brain morphologic features on magnetic resonance images are described and normative data are provided for six morphologic variables. An estimated function relating age (ranging from 8 to 79 years) to average values is given for each measure. A linear decrease over the age range is observed in the volume of the cerebrum. Linear increases are observed in measures of ventricular and sulcal fluid. A curvilinear decrease in cortical volume is found and is demonstrable even in young adults. Highly nonlinear increases in the volume of signal hyperintensities are observed in cortical and subcortical regions. The methods described may be used to provide an age-adjusted index of morphologic abnormality for each subject on any of the measures. They are currently in use in ongoing neurobehavioral studies of patients with nonfocal brain abnormalities and primary disorders of affect and cognition.