This study explored the relationship of driving anger expression to driving anger, trait anger, general anger expression, and aggressive and risky behavior while driving. Verbal, physical, and vehicular forms of expressing anger while driving correlated positively with each other, driving and trait anger, anger-in, and anger-out and negatively with adaptive/constructive driving anger expression and general anger-control. Adaptive/constructive expression formed small negative correlations with these measures, except for a positive correlation with anger-control. Regression models controlling for demographic variables and driving anger, trait anger, or general anger expression demonstrated forms of driving anger expression added variance to predicting aggressive and risky behavior. Forms of driving anger expression partially mediated the effects for driving anger, trait anger, and general anger expression on aggressive and risky behavior. No moderation effects were found for age, gender, or miles driven. Findings provided evidence for convergent and incremental validity for the Driving Anger Expression Inventory.