© 2016 American Academy of Allergy, Asthma & Immunology Background Anaphylaxis is a potentially life-threatening systemic allergic reaction. Objective We aimed to determine the incidence rate and causes of anaphylaxis during a 10-year period in Olmsted County, Minnesota. Methods Using the resources of the Rochester Epidemiology Project, a comprehensive records linkage system, we performed a population-based incidence study in Olmsted County, Minnesota, from 2001 through 2010. All cases with a diagnosis of anaphylactic shock and 20% of cases with related diagnoses were manually reviewed. The relationships of age group, sex, and year of anaphylaxis with incidence rates were assessed by fitting Poisson regression models. Results Six hundred thirty-one cases of anaphylaxis were identified. The median age was 31 years (interquartile range, 19-44 years). The overall age- and sex-adjusted incidence rate was 42 (95% CI, 38.7-45.3) per 100,000 person-years. There was a significant increase in the overall incidence of anaphylaxis during the study period, with an average increase of 4.3% per year (P < .001). In addition, there was a 9.8% increase per year in the incidence rate of food-related anaphylaxis. Food-related anaphylaxis was most common in children aged 0 to 9 years, venom-related anaphylaxis was most common in those 20 to 39 years of age, and medication-related anaphylaxis was most common in those 30 to 39 years of age. Conclusion The overall incidence rate of anaphylaxis was 42 per 100,000 person-years from 2001-2010 in Olmsted County, Minnesota. The incidence of anaphylaxis increased over time, and several inciting triggers were uniquely associated with different age groups.