The present study examines co-offending groups that commit violent firearms offences within the UK, in order to develop an understanding of these groups in terms of their level of professiolism. A sample of 69 cases was selected from two British law databases, consisting of offences that involved the utilization of a firearm in a violent crime committed by more than one offender. Cases were content alysed for offending behaviour. The presence of a three-way thematic model of crimil professiolism, previously identified in robbery, was tested using multi-dimensiol scaling. Three themes of offences were identified as Targeted, Gratuitous and Reactive, which differed in the level of professiolism displayed. Gratuitous was the most common theme for the sample, demonstrating some evidence of planning but also gratuitous violence towards victims. In conclusion, while violent gun crime is typically a phenomenon involving young males, not all groups display the same behaviour or levels of professiolism, as is evident in the existence of all three themes. These differences are important for understanding the psychology of the offences and designing operatiol responses.