This paper presents a longitudinal study of the relationship between personality, coping, chronic stress, social support and posttraumatic stress disorder (PTSD). A hypothesized model of the relationship between the predictor variables and PTSD symptoms was proposed. Path analyses was completed to test the model. One hundred fifty-eight adult burn survivors completed questionnaires measuring each of the variables in the hospital. Of those 124 and 94 completed the PTSD measure at 1 month and 6 months postdischarge, respectively. The hypothesized model fit the data at each time point with slight variations. The model accounted for 46 and 29% of the variance of PTSD symptoms at hospitalization and 1 month. Neuroticism was the most important personality dimension in predicting PTSD. Avoidant Coping and Social Support mediated a high percentage of the relationship between Neuroticism and PTSD. The best predictor of PTSD symptoms at 1 and 6 months was PTSD symptoms at hospitalization.