The policing of rape and serious sexual offences (RASSO) is increasingly under scrutiny, with rising reporting rates, high attrition rates, and ever-decreasing charge and conviction rates. Internationally there appear to be common inadequacies in RASSO investigations. Given these issues, policing specialism may be an effective tool to improve the investigation of RASSO. This article systematically draws together the existing literature from around the world on the use of a specialist approach to tackling RASSO. A systematic literature review was conducted, and 18 papers were included for analysis based on the inclusion/exclusion criteria. From these documents, five key themes were found: investigation procedures and processes; victim care; specialist training, knowledge and skills; officer wellbeing and capacity; and policing outcomes. The review highlighted that the specialist policing of RASSO can improve the investigative process on several levels: improving the efficacy of the individual components of the investigation; better engagement with victims; better officer wellbeing; and overall improved policing outcomes. Further research is required into the specific mechanisms that results in improvements into the investigative process, the set-up of such specialist units, as well as how training in this area can be as effective as possible.