Despite a mutual interest in disordered behavior, the psychological approaches of individual differences and behaviorism historically have had little common research or discourse. Moreover, over time, both fields independently have developed methods of assessment and treatment that--despite being broadly applicable across populations--exist only in parallel. This also is despite the facts that (1) individual differences frequently are defined by specific types of behavior (or lack thereof), and (2) behavioral analyses may include "organism" variables that share features with temperament variables. The primary goal of the current study is to examine relations between broad temperament factors and the function of problem behavior(s) identified through formal clinical assessment. The proposed model hypothesizes unique contributions of extraversion/surgency/positive affectivity (E/SPA) and neuroticism/negative affectivity (NNA) to the behavior functions of attention and escape, respectively. Subsidiary goals of the study included replicating previously identified temperament factors in this sample and assessing relations among temperament scales and behavioral form(s). Fifty-three children and their caregivers were recruited from 4 behavior treatment clinics at the University of Iowa. Caregivers were asked to complete two measures of temperament/personality: the Children's Behavior Questionnaire Short Form (CBQ) and the Schedule for Nonadaptive and Adaptive Personality--Other Report Form (SNAP-ORF). Children also underwent behavior assessment procedures as part of their scheduled clinic appointment, and these records were subsequently accessed to code function, form, frequency, and severity of problem behaviors. Results showed significant, positive relations between E/S-PA and measures of attention function. These findings were consistent across several (though not all) measures of E/S/PA and attention function. In contrast, no significant relation between N-NA and either escape or attention was found. Structural modeling of temperament/personality was broadly consistent with the three factors proposed by the CBQ and SNAP-ORF. Several unique findings at the lower order trait level also were noted and are discussed. The results from the current study provide an important first step in linking behavior and personality with regard to function in addition to behavioral form. Implications for the definitions of traits and function used in this project are discussed. Future research should expand on these preliminary findings to replicate and clarify relations among individual differences and behavioral functions.