We examined 137 incidents of potentially lethal, weapon-enabled, targeted violence at health care facilities between 2008 and 2017 in the U.S. using open-source data. Individually held grievances by the perpetrator were commonly present. Perpetrators most commonly targeted one person, though collateral victimization did occur. Two thirds of cases involved at least one fatality. Firearm use outnumbered other forms of attack, followed distally by stabbing, blunt force trauma, and strangulation. Hospitals and residential care facilities represented the overwhelming majority of venues; patient rooms, main corridors/waiting areas, and parking areas were the most common locations of attack within facilities. Various attack characteristics, including weapon choice, perpetrator and victim relationship to the venue, incident location within a venue, were more frequently observed for certain motivations. Incidents involving an existing/former intimate relationship between the perpetrator and victim represented the largest proportion of cases. Preincident warning behaviors were most likely reported in cases motivated by disgruntlement with a perpetrator's own care or by intimate partner animus (IPA), and least likely in cases motivated by "mercy" or despondence over a loved one's health. These attacks usually continued until concluded by the perpetrator; perpetrator suicide occurred in a minority of cases. Potential mitigation measures are proposed for threat assessment professionals and facility staff. Public Significance StatementOur study revealed differences in perpetrator, attack, and victim characteristics based on motive for attack and expanded the current literature body on targeted attacks by including multiple types of health care facilities and weapons. The findings highlight unique vulnerabilities associated with each motive.