Inclusion Criteria:

• Limited to early problem drinkers (i.e., those with no more than mild alcohol dependence).
• Have an average weekly alcohol consumption of greater than or equal to 24 standard drinks for men and 18 standard drinks for women.
• Able to read English at the eighth grade or higher level and show no evidence of significant cognitive impairment.
• Willing to provide a collateral informant for interviews regarding the patient's drinking during the study.
• A woman of child-bearing potential must be non-lactating, practicing a reliable method of birth control, and have a negative pregnancy test prior to initiation of treatment.
• Willing to provide a signed informed consent to participate in the study.

Exclusion Criteria:

• Have a current clinically significant physical disease or abnormality.
• Have a serious psychiatric illness.
• Have a current diagnosis of drug dependence (other than nicotine dependence) or a lifetime diagnosis of opioid dependence.
• A current diagnosis of alcohol dependence that is moderate or greater in severity or a history of alcohol withdrawal, or recurrent use of alcohol to alleviate alcohol withdrawal symptoms.
• Used opioids or other psychoactive medications regularly in the month prior to study enrollment.
• History of hypersensitivity to naltrexone (Revia).