Background. In recent years, pharmacists have become more active in patient care and can demonstrate a positive impact on the outcomes of drug therapy in asthma patients. Objective. The primary objective of this systematic review was to assess the impact of asthma improvement strategies used by pharmacists. The secondary objective was to ascertain if these strategies improve the control and other direct outcomes for patients with asthma compared with no intervention. Methods. Electronic databases were searched from January 2006 to February 2012. Data abstracted from publications included publication details, participants/ setting, intervention study design, outcome measures, and key findings. Results. Forty-seven studies were initially identified; 8 matched our inclusion criteria. Four were US studies and 4 were Canadian. Published studies provided evidence of the clinical effectiveness of pharmacy services in asthma interventions. The role of pharmacists in disease diagnosis, access to private area for consultation, time, and staff support were highlighted as the key barriers to asthma intervention. Reimbursement for consulting services provided a unique opportunity for pharmacists to provide direct patient care. Conclusion. The review demonstrated the contribution of pharmacy-based services to the monitoring, counseling, and educating in asthma care. The evidence supports the wider provision of asthma intervention through pharmacy services. Well-designed studies on the effectiveness of pharmacists' interventions to improve outcomes of patients with asthma need to be performed. In addition, further research is needed regarding the contribution of pharmacy services to disease detection as part of local public health strategies.