DATA WERE COLLECTED FOR THIS FIFTH NATIONWIDE SURVEY FROM A SAMPLE OF 4,594 PERSONS ABOVE THE AGE OF 12. INTERVIEWING WAS CONDUCTED DURING APRIL THROUGH JULY, 1977, USING THE RESPONSE ANALYSIS CORPORATION NATIONAL AREA PROBABILITY SAMPLE. THE SAMPLE INCLUDED A WELL DISPERSED AREA CONSISTING OF 103 PRIMARY SAMPLING AREAS SELECTED FROM THE COTERMINOUS UNITED STATES; EACH AREA WAS RELATIVELY HETEROGENEOUS. DATA OBTAINED FROM INTERVIEWS WAS WEIGHTED TO COMPENSATE FOR DIFFERENCES IN PROBABILITIES OF SELECTION ASSIGNED TO VARIOUS PROPULATION SUBGROUPS AND TO ADJUST FOR DIFFERENCES IN INTERVIEW COMPLETION EXPERIENCE. ACTUAL DATA COLLECTION INSTRUMENTS INCLUDED TWO INTERVIEW FORMS, A SELF-ADMINISTERED QUESTIONNAIRE ON MARIHUANA, AND SEVEN ANSWER SHEETS DEALING WITH PARTICULAR KINDS OF DRUGS. GREAT CARE WAS TAKEN TO ENSURE THE CONFIDENTIALITY OF INFORMATION PROVIDED, AND RESPONDENTS WERE REIMBURSED THREE DOLLARS FOR PARTICIPATION. WITH REGARD TO RESPONDENT COOPERATION AND UNDERSTANDING, 93.8 PERCENT OF ALL YOUTH WERE VERY COOPERATIVE, AS WERE 89.6 PERCENT OF ALL ADULTS. THE SPECIFIC RESPONSE RATE FOR THE NATIONAL SURVEY WAS 80 PERCENT. STATISTICAL DATA AND NUMEROUS EXHIBITS (INTERVIEW SHEETS) ARE PROVIDED. THE MAIN FINDINGS OF THE STUDY ARE INCLUDED IN VOLUME I, NCJ #528940. (LWM)