A method for notifying a remote facility of a vehicle accident, the method comprising the steps of: providing a system comprising impact sensors placed on the vehicle at multiple locations; storing the locations of the impact sensors when the vehicle is in a stationary position to provide a library of stationary locations; determining the location of each impact sensor in the event of an impact; determining if any impact sensor has been displaced from its stationary location as a result of the impact; determining the severity of the impact by calculating the extent of displacement of each impact sensor from its stationary position; and automatically informing the remote facility that there has been an accident if it is determined that the extent of displacement as a result of the impact is greater than a pre-determined amount; characterised in that each impact sensor is configured to communicate with at least one of the other impact sensors and the step of determining if any impact sensor has been displaced from its stationary location on impact includes the step of creating a communication path between an impact sensor and at least one of the other impact sensors thereby to determine the location of each impact sensor as a result of the impact and using the library of locations to compare the location of each impact sensor after impact with its stationary location to determine an extent of displacement and if the extent of displacement exceeds a threshold value automatically informing the remote facility, wherein the step of determining the location of each impact sensor includes measuring the distance between impact sensors, and wherein the step of creating a communication path to determine the location of an impact sensor includes the step of measuring the distance between the impact sensor and at least one other impact sensor. providing a system comprising impact sensors placed on the vehicle at multiple locations; storing the locations of the impact sensors when the vehicle is in a stationary position to provide a library of stationary locations; determining the location of each impact sensor in the event of an impact; determining if any impact sensor has been displaced from its stationary location as a result of the impact; determining the severity of the impact by calculating the extent of displacement of each impact sensor from its stationary position; and automatically informing the remote facility that there has been an accident if it is determined that the extent of displacement as a result of the impact is greater than a pre-determined amount; characterised in that each impact sensor is configured to communicate with at least one of the other impact sensors and the step of determining if any impact sensor has been displaced from its stationary location on impact includes the step of creating a communication path between an impact sensor and at least one of the other impact sensors thereby to determine the location of each impact sensor as a result of the impact and using the library of locations to compare the location of each impact sensor after impact with its stationary location to determine an extent of displacement and if the extent of displacement exceeds a threshold value automatically informing the remote facility, wherein the step of determining the location of each impact sensor includes measuring the distance between impact sensors, and wherein the step of creating a communication path to determine the location of an impact sensor includes the step of measuring the distance between the impact sensor and at least one other impact sensor.