Stalking is a significant social issue. The inconsistency as to what defines stalking has resulted in the creation of different methods to measure the crime. However, there has been minimal work done that assesses the severity of individual stalking behaviors. The aim of the present study was to assess the level of stalking behavior in terms of severity within a randomly selected sample of 924 cases from the database of the National Stalking Helpline. Item response theory analyses were used to assist in developing a scale that displays the ranking order of each stalking behavior. These analyses were also used to examine whether the stalking behavioral items created a single continuum of severity of stalking. Results indicated that 16 stalking behavioral items of the 28 items present in the National Stalking Helpline, best represented the severity of stalking. Unwanted communication behaviors such as text messages and phone calls were located at the lower end of the severity scale, whereas criminal damage and death threats were mapped on the higher end of the continuum. The findings also revealed that the 16 items categorized under 6 factors. The findings of the present study provide many implications for stalking agency professionals and criminal justice responses.