YOUNG ALCOHOL ABUSERS IN THE UNITED STATES NAVY ARE TREATED IN SEPARATE PROGRAMS FROM YOUNG DRUG ABUSERS. HOWEVER, SINCE MOST SAILORS ADMITTED TO THESE PROGRAMS ARE POLYDRUG ABUSERS, TREATMENT PERSONNEL HAVE FELT IT APPROPRIATE TO TREAT BOTH GROUPS TOGETHER. THIS STUDY WAS UNDERTAKEN TO COMPARE THE SOCIAL AND PSYCHOLOGICAL CHARACTERISTICS AND TREATMENT SUCCESS OF TWO GROUPS OF PRIMARILY ALCOHOL ABUSERS, 25 YEARS-OF-AGE OR LESS. ONE GROUP ADMITTED ILLEGAL DRUG ABUSE 6 MONTHS PRIOR TO TREATMENT. THE SECOND GROUP ABUSED ONLY ALCOHOL. THE SAILORS WERE COMPARED ON DEMOGRAPHY, MILITARY DISCIPLINE HISTORIES, PHYSICAL SYMPTOMS, PERSONALITY, AND ATTITUDE TOWARDS NAVAL SERVICE. THE EFFECTIVENESS OF TREATMENT, DEFINED AS RETURN TO ACTIVE DUTY STATUS OR RECEIPT OF A FAVORABLE DISCHARGE WITH RECOMMENDATION FOR REENLISTMENT, WAS ALSO COMPARED. NO DIFFERENCES BETWEEN GROUPS WERE FOUND FOR DEMOGRAPHY, PHYSICAL SYMPTOMS, PROBLEMS RELATED TO ALCOHOL ABUSE, MILITARY DISCIPLINE HISTORIES, OR TREATMENT EFFECTIVENESS. PERSONALITY SCALES DIFFERED, HOWEVER, REFLECTING MORE MATURITY AND SOCIAL CONFORMITY AMONG ALCOHOL-ONLY ABUSERS. SIGNIFICANT POSITIVE CHANGES IN EMOTIONAL STABILITY AND EXTRAVERSION WERE OBSERVED IN BOTH GROUPS DURING TREATMENT. THE RESULTS INDICATE THAT ALCOHOL AND DRUG ABUSERS CAN BE TREATED IN THE SAME TYPE OF PROGRAM. THEREFORE, INFORMATION CONCERNING ILLICIT DRUG ABUSE BY MEN ADMITTED TO ALCOHOL REHABILITATION CENTERS SHOULD BE ROUTINELY COLLECTED. FURTHER, AN EXPERIMENTAL PROGRAM TO TREAT YOUNG SUBSTANCE ABUSERS TOGETHER SHOULD BE INSTITUTED. TABLES SHOWING STUDY DATA STATISTICS, AND A SMALL LIST OF REFERENCES ARE GIVEN. (JMB)