Asthma treatment guidelines are intended to relieve symptoms and to prevent complications such as exacerbations, airway remodeling, and death. The existing recommendations are based on a combination of evidence and expert opinion. Recent data raise questions about the need for chronic controller therapy for those patients at the very low end of the asthma-severity continuum. Although these data are not sufficient to warrant a change in guidelines, the new information points out the need for large, long-term studies on the treatment of mild persistent asthma, with an emphasis on exacerbations, remodeling, and the relationship between these outcomes and markers of asthma control.