Asthma affects a considerable proportion of the population worldwide and presents a significant health problem in Australia. Given its chronic nature, effective asthma self-management approaches are important. However, despite research and interventions targeting its treatment, the management of asthma remains problematic. This study aimed to develop, from a theoretical basis, an asthma self-management model and implement it in an Australian community pharmacy setting in metropolitan Sydney, using a controlled, parallel-groups repeated-measures design. Trained pharmacists delivered a structured, step-wise, patient-focused asthma self-management program to adult participants over a 9-month period focusing on identification of asthma problems, goal setting and strategy development. Data on process- clinical- and psychosocial-outcome measures were gathered. Results showed that participants set an average of four new goals and six repeated goals over the course of the intervention. Most common goal-related themes included asthma triggers, asthma control and medications. An average of nine strategies per participant was developed to achieve the set goals. Common strategies involved visiting a medical practitioner for review of medications, improving adherence to medications and using medications before exercise. Clinical and psychosocial outcomes indicated significant improvements over time in asthma symptom control, asthma-related self-efficacy and quality of life, and negative affect. These results suggest that an asthma self-management model of illness behaviour has the potential to provide patients with a range of process skills for self-management, and deliver improvements in clinical and psychosocial indicators of asthma control. The results also indicate the capacity for the effective delivery of such an intervention by pharmacists in Australian community pharmacy settings.