He has been involved in Chronic Obstructive Pulmonary Disease (COPD) policy including the national Outcomes Strategy for COPD and clinical lead for the National COPD Audit in Primary Care. His current research interests are in severe asthma, COPD and pulmonary rehabilitation. Working with many international collaborators, he runs global health projects funded by Horizon 2020 and MRC / Wellcome and DFIID relating to lung disease in Uganda, Vietnam, Greece and Kyrgyzstan. He developed the Lung Information Needs Questionnaire and the DOSE Index for COPD severity assessment, and now the Severe Asthma Quality of Life Scale. He has published over 60 papers and several books.