Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) and other fibrotic interstitial lung diseases (AE-ILD) is defined by significant acute respiratory worsening and new widespread alveolar damage. This review summarises the current knowledge of diagnosis and treatment of these events. The diagnosis of AE-IPF and AE-ILD is based on typical HRCT findings of new and bilateral ground glass opacification and/or consolidation, and exclusion of fluid overload or cardiac failure. Treatment relies, despite low quality of evidence, on glucocorticoid in addition to supportive and palliative treatment. Despite treatment, the prognosis is poor, with a median survival of 2-4 months.