This Practice Note highlights the practical steps which need to be considered by those advising on the immediate aftermath of a serious health and safety workplace accident in England, Wales and Scotland. It also includes consideration of the reporting requirements under the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013 (RIDDOR), SI 2013/471, explains which regulators will become involved in the investigation, identifies the responsibilities of duty holders following a workplace incident as well as explaining the scope of an internal investigation into the suspected health and safety breaches and the issues to consider when dealing with the investigating authorities.