GCS assessment is an essential skill for professionals caring for neurologically impaired individuals. A clear understanding of the principles underpinning GCS assessment, knowledge of GCS assessment and its documentation, and an awareness of the confounding factors and limitations of assessment are prerequisites for evidence-based, competent and safety-focused assessment. It should be highlighted that the GCS assessment is an assessment of level of consciousness, forming part of a neurological assessment, but is not a neurological assessment in itself. A standardised approach across healthcare professionals is central to consistency in application and, ultimately, to accurately detecting changes in level of consciousness between assessors and care settings. Students and healthcare practitioners should be educated about how to undertake a GCS assessment in a standardised manner. The theoretical components that underpin the GCS should be taught alongside the opportunity to practise the skills. Such application of the theoretical knowledge allows practitioners to think critically about the findings, in the context of the person/ situation they are assessing. This international standard for education and practice with adults has been written by neuroscience specialist practitioners from across Europe. It provides authoritative, evidence-informed guidance to improve the quality of education specific to the use of the GCS tool, with the aim of increasing knowledge and skills and improving the safety of those in our care.