In spite of sensitivity to right frontal lobe dysfunction, the Design Fluency Test (DFT) has been limited by one global score with little psychometric data. This study developed an expanded scoring system with standardized instructions for multiple dimensions of design performance and provided reliability and validity data in a college (n = 64) and diverse neuropsychological sample (n = 165). The scoring system allowed reliable scoring of number of novel designs, complexity of designs, variations in designs, and concrete, frankly perseverative, and scribbled responses. Performances for a college sample were relatively stable at 1-month retest, but showed practice effects for number of novel designs and complexity. Two principal components showed modest, expected relationships to other neuropsychological measures in the clinical sample. Clinical subjects with a history of closed-head injury or dementing disorder showed impaired DFT performances, with complexity the most sensitive indicator of impairment.