AbstractThe Internet and social media have grown increasingly relevant in homicide cases in recent years. Although several recent studies have analyzed the relationship between homicide and the Internet, there is a dearth of rigorous scientific research on the subject to date. Although a statistically rare event, Internet‐related homicide may be increasing, and forensic mental health professionals may experience growing demand for consultations in cases where the Internet and social media play a salient role. Understanding some of the ways in which homicide perpetrators have used the Internet can help to inform case formulation and threat assessments in these cases. This article reviews several key themes, including the use of the Internet as a source of information in the commission of homicide, its use to target victims, the spread of self‐publishing and multimedia sharing, conflict escalation through social media, and the threat posed by Internet extremist communities. Finally, suggestions are made to help inform future research regarding the relationship between homicide and the Internet.