(1) Determine and compare prevalence of forms of anger (FOA; anger, hostility, aggression, anger-in, anger-out, chronic anger) in community nonpatients (n=478), community patients (n=158), acute pain patients (APPs; n=326), chronic pain patients (CPPs; n=341); and (2) develop FOA predictor models in APPs and CPPs. A large set of items containing the FOA items was administered to the above groups, who were compared statistically for FOA endorsement. APPs and CPPs affirming the anger and chronic anger items were compared with those not affirming on all available variables including the Battery for Health Improvement (BHI-2) with significant variables (P≤0.001) utilized in predictor models for anger and chronic anger in APPs and CPPs. Setting community plus rehabilitation facilities. FOA affirmation ranged from 8.28% for chronic anger in nonpatients to 37.54% for anger in CPPs. Only CPPs were more likely to affirm anger (P≤0.04) and chronic anger (P≤0.01) at a significantly higher rate than community patients. In both APPs and CPPs, all FOA items except anger management-in were significantly correlated with other FOA items. For anger and chronic anger for CPPs and APPs, hostility was the strongest predictor. All models predicted anger and chronic anger significantly better than the base rate prediction. According to the results of this study anger and chronic anger are more frequently found in CPPs vs. community patients supporting the clinical perception that many CPPs are angry. As such,clinicians should actively screen CPPs for the presence of anger in order to engage these CPPs in anger management treatment.