The purpose of this article is to provide evidence for the validity of performance curve classification on the nonverbal subtest of the Validity Indicator Profile (VIP-NV). A four-fold classification scheme of performance on cognitive testing is proposed. This scheme combines effort and motivation to generate four response classifications: compliant, careless, irrelevant, and malingering. Data are presented across six studies from cognitive and personality testing for 737 male pretrial criminal defendants. Additionally, computer-generated VIP-NV performances were subjected to four levels of randomization to investigate VIP-NV carelessness indicators. The findings support the validity of the four-fold classification scheme and support the classification of response on the basis of motivation and effort. Published by Elsevier Science Ltd