Thirty years have passed since the Korean Association of Pediatric Allergy and Respiratory Disease was founded. There have been great changes in the pattern of respiratory diseases in Korean children during the last 30 years with economic development in the country. Pneumonia remains the leading cause of childhood morbidity, despite advances in the prevention and management. The incidence and mortality of pneumonia caused by typical bacterial pathogens have been reduced. However, the predominance of Mycoplasma pneumoniae or virus-associated diseases is emerging, which suggests that novel diagnostic and therapeutic strategies are needed. Viral bronchiolitis is one of the most substantial health burdens for infants and young children worldwide. Although respiratory syncytial virus is the most common pathogen, molecular diagnostic techniques have identified many other viruses including human rhinovirus causing bronchiolitis. Bronchiectasis is a chronic respiratory condition characterized by chronic infection, airway inflammation, and progressive lung function decline. Research into the interactions between early life respiratory infections and development of bronchiectasis is imperative to halt the disease in its origin and improve adult outcomes. Acute respiratory distress syndrome (ARDS) is a severe, life-threatening lung disease with diffuse inflammatory lung injury leading to pulmonary edema and hypoxia. Although many modalities to treat ARDS have been studied, supportive therapies and lung protective ventilator support remains the mainstay. This review focuses on the current trends in research on these childhood respiratory diseases through literature review and aims to investigate the impact of Korean study results in this field. (Allergy Asthma Respir Dis 2018;6 Suppl 1:S66-76)