### What you need to know
For patients with a traumatic brain injury or other acute brain impairment (such as stroke, infective cerebritis, or toxic encephalopathy), assessment of their clinical condition, and how it may change, is fundamental to their care. For almost 50 years, the Glasgow Coma Scale (GCS) has been used worldwide to assess a patient’s responsiveness, or level of consciousness,1 in acute brain impairment.2 When using the GCS, the response of a patient is documented in three components: eyes, verbal, and motor. Each of these components is assessed simultaneously. Over time, lessons learnt have prompted developments to support and extend the usefulness of the GCS. Awareness of the various GCS tools is useful for all doctors involved in the assessment or management of acutely unwell patients. This article offers an overview of the most recent updates, including the GCS Aid,3 GCS Pupils score (GCS-P),45 and the verbal imputation score.6 We discuss how to apply these too