Data generated from a survey of western dairy farms was used to determine the characteristics of dairy farmers who have undertaken to improve security measures on their farms during the past 2 or 3 yr. The findings suggest that decisions to improve on-farm security are influenced by the producer's awareness of how to develop a security policy, and by the size of the dairy operation. The results also support the notion that farms may be vulnerable to bioterrorist attacks because most farmers do not believe it is important to establish on-farm security policies.