Research on offending behavior rehabilitation suggests that offenders would gain the maximum benefit from programs that reflect the individual needs of different types of offender. Multivariate theories of offending behavior are thus required to inform individualized rehabilitation. The aim of the current study was to construct a multivariate model for the prolific offense of assault. Qualitative methodology was used to construct a descriptive model of assault for 25 adult assault offenders. The model incorporated the development of violent behavior, types of anger, violence motivation, and the assault offense. The model consisted of 14 categories, 10 of which allowed for individual differences in behavior. A total of 35 participant transcripts were then coded through the model where the individual differences occurred. Five main offense types were found. The characteristics of the types of assault offense gave indications for how rehabilitation may be targeted for each group.