Respiratory infections, frequently caused by drug-resistant bacteria, are the main cause of disease and death in people with cystic fibrosis (CF) and bronchiectasis (BE). Thanks to inhaled antibiotics, patients now live longer than ever before and enjoy a better quality of life. However, infections are increasingly becoming resistant to the few drugs available, putting patients¿ lives at risk. The iABC project is advancing the development of two inhaled antibiotics for patients with CF and BE. It is also working to identify ways of improving clinical trials of treatments for these serious diseases.