 This is a randomized, parallel, multicenter, 12-week study in adolescent and adult patients with mild-to-moderate asthma, to evaluate the efficacy and safety of Armstrongs Albuterol-HFA MDI, in comparison to a Placebo Control and an Active Control of Proventil-HFA. While Albuterol-HFA Treatment T and Placebo Treatment P will be double-blinded to both the subjects and investigational staff, the active comparator drug, Proventil-HFA Treatment R, can only be evaluator-blinded, due to: 1 its physical appearance differing from that of the T and P devices; and 2 unavailability of a Proventil-HFA placebo which would otherwise be used for a double-dummy design. All study medications will have the canisters and all product-identifying text or graphics e.g., molded text on actuator masked so that the treatments cannot be identified. No subject in any study arm will be given any information that could reveal the nature of the treatment given. All study subjects will be instructed not to reveal or discuss the study medications to the study staff or other subjects. The designated study evaluators, who conduct the clinical visits and safety and efficacy evaluations and perform the data recording and transcription, will be blinded to the study medications. 