He has published and lectured worldwide on quality in endoscopy, screening and colonoscopic surveillance, receiving the BSG Hopkins Endoscopy Prize in 2006 and 2020, and the RCP Goulstonian Lectureship in 2008. He co-authored BSG (2010), NICE (2011), European (ECCO, 2012) and SCENIC (USA, 2015) colitis surveillance guidelines, and was the lead author for the BSG/ACPGBI management of large non-pedunculated colorectal polyps guidelines (2015) and the BSG/PHE/ACPGBI post-cancer and post-polypectomy surveillance guidelines (2019).