Bronchial asthma is a heterogeneous disease in terms of the phenotypes, but the majority of patients, both children and adolescents, and adults suffer from IgE-dependent (atopic) asthma. This asthma phenotype most often is associated with allergic rhinitis, which defines systemic therapy for both diseases. The allergen-specific immunotherapy (SIT) meets that approach best of all. SIT is viewed as a treatment not for a specific nosology (rhinitis, asthma or atopic dermatitis), but for an allergen. The epidemiology and the etiology of atopic asthma, role of SIT in treatment of asthma, efficacy, safety, and basic mechanisms are discussed in the article.