Florence Nightingale undertook the first clinical audit during the Crimean War by reviewing conditions in British hospitals and identifying issues like contaminated water and inadequate sanitation. She implemented changes that reduced the death rate of British soldiers from 40% to 2% within six months. Clinical audits now systematically compare current practices to standards to improve patient care and outcomes. They highlight both deficiencies and best practices, promote evidence-based changes, and reinforce quality improvement as a core part of healthcare systems and professional responsibilities. The audit cycle involves identifying issues, setting criteria and standards, collecting data, identifying areas for improvement, implementing changes, and re-auditing to continue enhancing care.