This trial will attempt to investigate whether asthmatic patients that are well controlled with low-dose twice daily inhaled corticosteroid (ICS) therapy can safely be switched to other modes of controller therapy without loss of asthma control. Patients demonstrating good control on twice-daily low-dose ICS will be randomized to one of three treatment groups: once-daily low-dose ICS (fluticasone), leukotriene receptor antagonist (montelukast), or once-daily combination therapy (fluticasone-salmeterol).