Professor Tahir is a specialist advisor to the National Institute of Clinical Excellence (NICE) on tendinopathies (includes tennis elbow, plantar fasciitis, Achilles tendinopathy). He trained at Kings College London and completed his specialist training in both general medicine and rheumatology in the North Thames region. He is actively involved both in undergraduate and postgraduate training, education and clinical research.

Professor Tahir is the clinical lead for Rheumatology, Biological Therapies and Research and is a Chief / Principal Investigator for a large number of clinical trials investigating new biological treatments for autoimmune rheumatic disorders including rheumatoid arthritis, psoriatic arthritis and Ankylosing Spondylitis. He recently was awarded 2 NIHR wards, the most prestigious being the NIHR@ 10 awarded to only 5 researchers nationally. He is actively involved in both rheumatology and acute medicine and has recently been awarded the BSR Best Practice award for Best Emerging Practice.

Professor Tahir is the clinical lead for the training of overseas medical students and is also an international examiner for the MRCP PACES exam and the final year clinical exam at the Barts and London. He is the Training Programme Director for core medical training at his hospital and the winner of the Barts Health Innovations Awards 2016 for Service Improvement as well as a honorary Professor of Clinical Sciences at St Mathews University.