Dr Rees runs a weekly neurology clinic at Spire Bushey (Sunday mornings and Thursday evenings) and sees patients with all types of neurological symptoms including headaches, epilepsy, blackouts, pins and needles, Parkinson's disease, tremors, muscle weakness, poor balance and dizzy spells. A new patient consultation typically lasts 30 minutes and a follow-up consultation 15 minutes. If appropriate, he will refer you for MRI scans, EEG, EMG and other tests the majority of which can be done at Spire Bushey.

Dr Rees was appointed in 1999 as Clinical Senior Lecturer in medical neuro-oncology at the Institute of Neurology and Honorary Consultant Neurologist at the National Hospital for Neurology and Neurosurgery, University College London Hospital Trust and Royal Marsden Hospitals. He specialises in the management of low-grade brain tumours and paraneoplastic neurological syndromes.

He is the clinical lead for neuro-oncology in the UCLH Trust, Dr Rees runs the UCL neuro-oncology Research Group. He was the chair of the Brain Tumour working party for the Referral Guidelines Steering Group and is a member of the Brain Tumour Clinical Studies Group of the National Cancer Research Network.

Dr Rees is the module lead for Clinical Neurosciences teaching of medical students at University College London.