This article reviews the evidence demonstrating an interaction between problem drinkers and their family members, showing that there is a great deal of reciprocity between the presence of alcohol related problems, and marital and family problems, and that this reciprocity works in both directions. It then examines the considerable evidence ( both from reviews and within individual therapeutic areas) that therapeutic work aimed at improving family functioning leads to improved drinking outcomes. This body of evidence demonstrates that family members can assist problem drinkers with their drinking problems. There is also good evidence that the people who are more successful in controlling their drinking are those who are more stable before treatment: people who are in established and positive relationships with a spouse and/or a family are more likely to be stable, and hence to be successful at controlling their drinking. There is, however, only limited research-based evidence demonstrating that these two issues are linked: that family members are effective in assisting people who wish to control their drinking to do this. Much more hard evidence for this assertion needs to be developed.