The PICTS derives from lifestyle theory, which views habitual criminal behavior as a life pattern characterized by irresponsibility, self-indulgence, interpersonal intrusion, and social rule breaking. The 64 items that comprise the 8 PICTS thinking style scales were rationally sorted into 2 general content scales: a scale composed of items believed to reflect current criminal attitudes and beliefs, and a scale that references past criminal attitudes and beliefs. Items were eliminated that exhibited highly skewed distributions, failed to discriminate between custody levels, loaded weakly on the first factor of a principal components analysis, and displayed minimal differentiation in correlations with the two content scales. This resulted in a 13-item Current scale and a 12-item Historical scale. Using data analysis results attained by several different samples of offenders, divergent patterns of strength were revealed for the two content scales. The Historical scale demonstrated greater stability and correlated better with past criminality. The Current scale was more effective in predicting future disciplinary and release outcome. The two content scales may not only be helpful in establishing hypotheses for research on criminal thinking but they may also be of assistance in making certain clinical decisions. The sensitivity and specificity data denote that the content scales may be more effective in ruling out the presence of significant criminal thinking than in ruling in significant criminal thinking. The Current scale may be useful in predicting future criminality while the Historical scale assesses a person’s criminal past which may or may not coincide with current criminal attitudes and beliefs. 5 tables, 23 references, appendix