Traditional neuropsychological measures of executive functioning are difficult to employ in functional imaging and clinical trial contexts and have tremendous practice effects. They also have poor sensitivity and specificity, while test-retest reliability is often not assessed in computer-based tests. The present study evaluates some psychometric properties of a new Parametric Go/No-Go (PGNG) Task. The PGNG consists of three levels of difficulty assessing attention, set-shifting, and processing speed, with the two more difficult levels assessing inhibitory control. A total of 63 healthy control participants were recruited at two sites to evaluate the psychometric properties of the PGNG. The PGNG was found to have solid parametric characteristics and strong test-retest reliability. Modest convergent validity was also demonstrated with other executive-functioning tests. Learning effects were significantly less than those for the Trail Making Test. The present results provide solid initial support for the validity and reliability of the PGNG.