The purpose of this study was to assess the comorbidity between chronic pain and posttraumatic stress disorder (PTSD) and examine the extent to which PTSD is associated with changes in the multidimensional experience of pain in a sample of Veterans with chronic pain. It was hypothesized that Veterans with comorbid chronic pain and PTSD would report significantly higher scores on measures of pain intensity, pain behaviors, pain-related disability, and affective distress than Veterans with pain alone. Data were obtained from 149 Veterans who completed self-report questionnaires as part of their participation in a Psychology Pain Management program at a northeastern Department of Veterans Affairs health care facility. Analyses indicated that 49% of the sample met criteria for PTSD. A multivariate analysis of covariance was conducted with age, sex, pain duration, and depressive symptom severity as covariates. In partial support of our hypothesis, the presence of PTSD was found to contribute significantly to measures of affective distress, even after controlling for the effects of depressive symptom severity. The implications of these data are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)