Background: Eisenmenger syndrome is associated with substantial morbidity and mortality. There is no consensus, however, on mortality risk stratification. We aimed to investigate survival and predictors of death in a large, contemporary cohort of Eisenmenger syndrome patients. Methods: In a multicenter approach, we identified adults with Eisenmenger syndrome under follow-up between 2000 and 2015. We examined survival and its association with clinical, electrocardiographic, echocardiographic, and laboratory parameters. Results: We studied 1098 patients (median age, 34.4 years; range, 16.1-84.4 years; 65.1% female; 31.9% with Down syndrome). The majority had a posttricuspid defect (n=643, 58.6%), followed by patients with a complex (n=315, 28.7%) and pretricuspid lesion (n=140, 12.7%). Over a median follow-up of 3.1 years (interquartile range, 1.4-5.9), allowing for 4361.6 patient-years observation, 278 patients died and 6 underwent transplantation. Twelve parameters emerged as significant predictors of death on univariable analysis. On multivariable Cox regression analysis, only age (hazard ratio [HR], 1.41/10 years; 95% confidence interval [CI], 1.24-1.59; P<0.001), pretricuspid shunt (HR, 1.56; 95% CI, 1.02-2.39; P=0.041), oxygen saturation at rest (HR, 0.53/10%; 95% CI, 0.43-0.65; P<0.001), presence of sinus rhythm (HR, 0.53; 95% CI, 0.32-0.88; P=0.013), and presence of pericardial effusion (HR, 2.41; 95% CI, 1.59-3.66; P<0.001) remained significant predictors of death. Conclusions: There is significant premature mortality among contemporary adults with Eisenmenger syndrome. We report, herewith, a multivariable mortality risk stratification model based on 5 simple, noninvasive predictors of death in this population.