Asthma is an inflammatory condition. Traditionally bronchoalveolar lavage and bronchial biopsies obtained by bronchoscopy have been used to demonstrate inflammation. Induced-sputum is a non-invasive, reliable, reproducible and safer technique for monitoring inflammatory activity in patients with asthma. Studies have shown that induced-sputum measures aspects of inflammation distinct to that measured by bronchoalveolar lavage or bronchial biopsies. Numerous studies have suggested that induced-sputum is a potentially useful tool for early diagnosis of exacerbation, monitoring of therapy, identification of the lowest effective dose and assessing compliance in asthmatics. In this respect, we suggest that this test can be routinely used in the management of difficult asthmatics.