The Psychological Inventory of Criminal Thinking Styles (PICTS)-dimensional relationship was found but the Lifestyle Criminality Screening Form (LCSF)-taxon relationship failed to surface. When the four most valid and factorially meaningful PICTS scales were combined with the four LCSF subscales, there was clear and consistent evidence of dimensional structure in the criminal lifestyle. From the earliest writings on the criminal lifestyle to the most recent update, the assumption has been that the criminal lifestyle is dimensional or categorical. However, this is an assumption that has never been formally tested. Three taxometric procedures, mean above minus below a cut (MAMBAC), maximum eigenvalue (MAXEIG), and latent mode factor analysis (L-Mode), were applied to the LCSF, the PICTS, and a combination of the 2 in a group of 771 male Federal prisoners. It was hypothesized that the rating scale (LCSF) would demonstrate taxonic structure and the self-report measure (PICTS) would demonstrate dimensional structure. Table, figures and references