His current research aims focus around chronic lung infections, in particular idiopathic bronchiectasis and aspergillus, Pseudomonas and non-tuberculosis mycobacterial infections. He is presently investigating host susceptibility to these infections, in addition to the development of biomarkers to assist in the management of these conditions. He co-chaired the National bronchiectasis guidelines and co-wrote the European bronchiectasis guidelines and National non-tuberculous mycobacteria guidelines. He chaired the British Thoracic Society Specialist Advisory Group for respiratory infections (2013-2016) and is presently secretary of the European Respiratory Society respiratory infection group. He has helped set up national and European research networks, with funding to produce clinical bronchiectasis databases and is the recipient of several prestigious research grants. He also collaborates with Industry and is global, national and site principal investigator of multicentre international clinical trials. He has won young investigator of the year awards from the Royal Society of Medicine, the European Respiratory Society, the British Thoracic Society and the British Association of Lung Research. In addition, he has won prestigious awards from the American Thoracic Society, the Medical Research Society and the British Lung Foundation and was awarded the European Respiratory Society research award for innovation in non-tuberculous Mycobacteria in 2018.

His clinical interests include respiratory infection, particularly host defence abnormalities, bronchiectasis, primary ciliary dyskinesia, primary immunodeficiency, non-tuberculosis mycobacterial infections and cystic fibrosis. He also lead TB at the Royal Brompton and Harefield NHS Foundation Trust, and runs TB clinics at Chelsea and Westminster Hospital. He leads laboratory services at the Royal Brompton and Harefield NHS Foundation Trust as Clinical Director of Laboratory Medicine.