House dust mites are a major source of allergens in house dust and, thus, the main trigger of perennial allergic respiratory diseases [1–5]. Scientific research on the life cycle, diet, and reproductive behavior of dust mites and on the biology of mite allergens has uncovered mechanisms leading to the development of respiratory allergies and suggests measures that can minimize exposure to dust mite allergens. Here, we discuss the evidence linking house dust mite exposure and respiratory allergies and present the efficacy of avoidance measures and their scientific evidence.