Objectives: This recent study assesses the correlation of incidence- and reaction-related variables to predict acute and posttraumatic stress disorder in rescue workers after the catastrophe of Kaprun (2000) in Austria, Europe. Methods: In a prospective longitudinal study, 250 emergency medical personnel, crisis intervention teams and police officers were assessed using the Acute Stress Disorder Scale (ASD), the Posttraumatic Stress Diagnostic Scale (PDS) and an incidence and reaction-related questionnaire 6 weeks and 6 months after their mission. Results: After 6 weeks, 7.3% of the emergency medical personnel, 22.2% of the crisis intervention team workers and 25.7 of police officers suffered from ADS. At 6 months after the disaster, 6.3% of all rescue workers showed PTSD. The incidence-related predictors of PTSD assessed in the study were duration of the mission and early arrival at the site. Uncertainty about the help given was found to be a reaction-related predictor. Conclusions: This study provides further support for the usefulness of incidence,, and reaction-related factors to predict acute and posttraumatic stress disorder in rescue workers. These results will aid in the development of special prevention strategies for rescue workers.