"About 200,000 people per year in the UK require critical care for many different reasons, ranging from acute medical emergencies, to major trauma incidents such as serious road accidents (Batchelor, 2021). People who develop a critical illness and their families deserve the best treatment and care that can be provided, to optimize their health outcomes, experiences and quality of life. Excellence, however, requires appropriate interventions with a strong evidence base and practitioners who are competent to deliver treatment and care. The aim of Critical Care Manual of Clinical Nursing Procedures second edition is to detail the latest research and rationale for evidence-based procedures and competencies related to the provision of Adult critical care. As such, the manual is ideally placed to be used as a reference and resource for advancing critical care practice and education for nurses and the wider multi-professional team. This chapter describes how critical illness needs are classified, provides an overview of key national policies and discusses the role of the manual in the introduction of evidence-based practice. Whilst mainly focused on the context of critical care nursing within the United Kingdom (UK), the content is relevant to critical care practitioners worldwide"--.