Chronic airway diseases are a significant cause of morbidity and mortality worldwide, and their prevalence is predicted to increase in the future. Respiratory viruses are the most common cause of acute pulmonary infection, and there is clear evidence of their role in acute exacerbations of inflammatory airway diseases such as asthma and chronic obstructive pulmonary disease. Studies have reported impaired host responses to virus infection in these diseases, and a better understanding of the mechanisms of these abnormal immune responses has the potential to lead to the development of novel therapeutic targets for virus-induced exacerbations. The aim of this article is to review the current knowledge regarding the role of viruses and immune modulation in acute exacerbations of chronic pulmonary diseases and to discuss exciting areas for future research and novel treatments.