The diagnosis of food allergy requires responses to two important questions: Does the patient have a food allergy? If so, which foods will elicit allergic symptoms? The first question will most often have to be answered following a physical examination and an interview with the patient and/or caretakers. Based on this, a provisional decision to pursue a food allergy diagnosis may be made after carefully considering other possible reasons for an adverse reaction to a food: aversion, infection, intoxication, or an underlying metabolic disease. To respond to the next question, the anamnesis is highly important in selecting which tests and, ultimately, oral food challenges the patient should undergo to reach the final diagnosis. For the diagnosing doctor, it is important to know and consider the regional pattern of inhalation and food allergies, the food consumption patterns in the local community, and the selection of patients - in terms of both age groups and symptoms - visiting the center. © 2015 S. Karger AG, Basel.