Patients' and physicians' knowledge of asthma control and risks can affect long-term outcomes. The Asthma General Awareness and Perceptions II (Asthma GAP II) survey sought to assess the beliefs and behaviors of asthma patients and their physicians. In the United States, a telephone survey was conducted among 1885 adults with asthma (representative population sample [n = 1001] plus additional black [n = 436] and Hispanic samples [n = 448]) who took asthma medication in the previous year. An online survey included 300 primary care physicians. Most patients (66, 84, and 78% of national, black, and Hispanic samples, respectively) and physicians (80%) considered asthma a very or extremely serious condition. In contrast to current guidelines, most patients (69, 72, and 70%) believed that quick-relief medications could be taken daily. Many patients (42, 52, and 60%) and some physicians (22%) stated controller medications could be taken less regularly when symptoms decrease, although most patients (92, 92, and 89%) and physicians (95%) indicated that controller medications are most effective when taken daily. Of patients who discontinued controller medications (21%), 71% discontinued when symptoms abated. Most physicians (87%) believed that patients discontinued controller medications without their advice. After controller medication cessation, more black (22%) and Hispanic patients (22%) than patients in the national sample (15%) experienced serious health consequences after an asthma attack. Gaps exist between patients' understanding of asthma control and their use of controller and quick-relief medications. Many patients and physicians fail to recognize that, even with symptom abatement, serious asthma risks remain.