This chapter explores the notion that families function as a unit, developing patterns of interaction that determine how people are supposed to be with one another. In families dealing with substance abuse, these interactions tend to become restricted as the family organizes around the use of the substance. This usually comes in the form of protecting the family from outside systems—by having rules about not talking to others, or even themselves, about the drug use. Over time, the family adapts and changes by the severity of the drug use and its impact on various family members. As this is happening, the family reconfigures the rules of the system to develop a new homeostasis so that it can function—however well or poorly that might be. The chapter presents an overview of alcoholic family types, phases of the alcoholic family, and a family typology of addiction.