Pulmonary exacerbations (PEx) are significant life events in people with cystic fibrosis (CF), associated with declining lung function, reduced quality of life (QoL), hospitalisations and decreased survival. The adult CF population is increasing worldwide, with many patients surviving prolonged periods with severe multi-morbid disease. In many countries the number of adults with CF exceeds the number of children, and PEx are particularly burdensome for adults as they tend to require longer courses and more intravenous treatment than children. The approach to managing PEx is multifactorial and needs to evolve to reflect this changing adult population. In this review, we discuss PEx definitions, precipitants, treatments and the wider implications to healthcare resources. We review current management strategies, their relevance in particular to adults with CF, and highlight some of the gaps in our knowledge. A number of studies are underway to try to answer some of the unmet needs, such as the optimal length of treatment and the use of non-antimicrobial agents alongside antibiotics. We provide an overview of these issues, concluding that with the changing landscape of adult CF care, the definitions and management of PEx may need to evolve to enable continued improvements in outcomes across the age spectrum of CF.