Increases in anger and hostility are commonly found after military deployment. However, it is unknown how anger and hostility develop over time, and which veterans are more at risk for developing these complaints. Data of 745 veterans one month before deployment to Afghanistan and one, six, twelve and 24 months after deployment were analyzed in a growth model. Growth mixture modeling revealed four classes based on their growth in hostility. Most of the participants belonged to a low-hostile group or a mild-hostile group that remained stable over time.