Abstract Prior research reveals a clear need to distinguish between homicides committed by solo offenders and those who act with another person. Moreover, as gender is considered in homicides, the dynamics of the offense change. This study examined homicide incidents by several offender combinations that consider gender and number of offenders. We rely on 2006–2010 National Incident-Based Reporting System (NIBRS) data (N = 12,441). The findings indicate that male solo offenders commit the majority of homicides. When offenders act with other offenders, the characteristics of the offense and offender vary. Multi-offenders were more likely than solo offenders to be younger and black. They also are more likely to have a concurrent offense and have either a stranger victim or related victim. When a female offender was present, the dynamics also varied from incidents where a female offender was not present. Incidents with a female offender present were more likely to have older offenders and co-offenders. Such...