Recent developments in the definitional literature on mental retardation emphasize the need to ground the concept of adaptive behavior in an expanded model of intelligence, which includes practical and social intelligence. Development of a direct measure of practical intelligence might increase the likelihood that an assessment of this domain would be included in the diagnostic process of mental retardation. The current paper reports on the preliminary exploration of the validity and utility of using a videotaped portrayal of everyday tasks, with built-in errors, as a measure of practical intelligence. A correlation of .79 was found between the practical intelligence video score and the Vineland domestic and community sub-domains score in 50 adults with mild and moderate mental retardation. This suggests that the instruments are essentially measuring the same domain of human competence. The unexplained variance may be attributed to the fact that the video measure is more directly measuring cognition.