In Occupational Health and Safety, an accurate understanding of what happened before and during an incident or accident is critical in developing an understanding of the various causes. Understanding root causes and the controls necessary to prevent incidents reoccurring can be both difficult and time consuming and, if not undertaken properly, can lead to ineffective measures and adverse recurrent events. A critical part of any accident investigation is the effective gathering of facts. One of the ways to acquire important first hand information is through witness statements. Given the crucial role of eyewitness evidence, statements should be obtained as soon as possible after an incident. This is not often possible due to demands on staff resources, lack of trained staff being available or the geographically remote location where the event has occurred. This paper examines the development of a self-administered witness interview tool, known as the SAW-IT™, and the theory used to elicit a comprehensive statement of events. This deceptively simple methodology, presently used by several Police Forces in criminal investigations, could be applied in the both in the Oil and Gas industry and in other spheres. This paper discusses the practical and cultural issues that have to be considered. Results of two studies will be outlined, both providing evidence that the interview tool elicits detailed and highly accurate information from witnesses. Study 2 demonstrates that the SAI also protects against forgetting which is a further benefit should a subsequent interview be necessary. Case studies demonstrating the use of the SAW-IT™ in an HSE investigation will be provided as illustrative examples of the practical and evidential benefits of the recall tool. The practical lessons and benefits in applying the SAW-IT™ tool in the oil and gas industry are shared and an outline given of further work proposed.