peer reviewed ; Asthma is a chronic heterogeneous airway disease. There are different asthma inflammatory phenotypes with various responses to treatment and different disease severities. When asthma requires chronic systemic corticosteroids or hospitalizations despite maximal inhaled therapies in asthmatic patients in whom comorbidities have been managed and who are considered as compliant, the pulmonologist may propose biological treatment to reduce exacerbations and the dose of systemic corticosteroids. During the last ten years, the number of biologics for the management of type-2 severe asthma has increased. Anti-IgE monoclonal antibodies (omalizumab) are available for more than ten years and recommended in severe allergic asthma. New biologics are now available to block IL-5 (mepolizumab, reslizumab) or its receptor (benralizumab). These treatments allow a reduction of exacerbations and of the dose of systemic corticosteroids, an improvement in asthma control, in asthma quality of life and for some of them, an increase in lung function. New biologics will soon be available in Belgium for the management of severe asthma. In addition to the improvement of asthma control in severe asthma, biological treatments have improved the understanding of the mechanisms leading to severe asthma.