Outlaw motorcycle gangs (OMGs) are an iconic element of the criminal landscape in the United States, the country of their origin. Members of OMGs may present to the emergency department (ED) as a result of motor vehicle accidents or interpersonal violence. When one member of an OMG is injured, other members and associates are likely to arrive in the ED to support the injured member. The extant literature for ED personnel lacks an overview of the culture of OMGs, a culture that promotes the display of unique symbols and that holds certain paraphernalia as integral to an outlaw biker’s identity and pride. The objective of this manuscript is to discuss various aspects of the culture of OMGs so that ED personnel may better understand the mentality of the outlaw biker. Knowledge of their symbols, values, and hierarchy can be crucial to maintaining order in the ED when an injured outlaw biker presents to the ED. We used standard search engines to obtain reports from law enforcement agencies and studies in academic journals on OMGs. We present the observations of 1 author who has conducted ethnographic research on outlaw bikers since the 1980s. [West J Emerg Med. 2014;15(4):523-528.]