The CHRONICLE Study is a multi-center, non-interventional, prospective cohort study of adults with severe asthma who do not achieve control with high-dose ICS therapy with additional controllers and/or require systemic corticosteroid or monoclonal antibody therapy. This study will provide a contemporary description of the epidemiology and medical management of United States adults with severe asthma who have not achieved control with high-dose ICS therapy and additional controllers. Additionally, the study will describe the use of and outcomes associated with recently approved monoclonal antibody therapies for severe asthma. Patients will be enrolled from a diverse population of academic and community-based specialist centers across the US. Data will be collected in a naturalistic manner and patient management will not be influenced by the study protocol. At least 1500 patients in the US with a confirmed diagnosis of severe asthma will be enrolled by a diverse set of asthma specialists (eg, allergists and pulmonologists who treat asthma) from academic and community-based centers. Basic de-identified information will be collected for all patients meeting study inclusion criteria, including those not approached for enrollment or who decline enrollment, to enable an assessment of the enrolled and non-enrolled populations. This information will include age, sex, insurance status, age at asthma diagnosis, class of asthma treatment per study inclusion criteria, number of asthma exacerbations in the past 12 months, study eligibility, whether the patient was approached for enrollment, study enrollment status, and reason for not enrolling for those who are approached but do not enroll. Patient-reported asthma control (Asthma Control Test [ACT]), asthma exacerbations, and treatment adherence will be solicited monthly. Patient-reported information on asthma-related healthcare utilization, global evaluation of treatment effectiveness (GETE), and work productivity (Work Productivity and Activity Impairment Asthma questionnaire [WPAI-Asthma]) will be collected at baseline and approximately every 3 months. Detailed information on asthma-related quality of life (Saint George's Respiratory Questionnaire [SGRQ]) as well as presence of an asthma treatment plan will be collected from patients approximately every 6 months. All of the questionnaires will be collected via web-based surveys. Patients will then be followed until study discontinuation or the patient withdraws from the study or death, whichever occurs first. The expectation is that patients will be followed for a period of at least 3 years.