Results from the Monitoring the Future's 2005 nationwide survey of 8th, 10th, and 12th grade students are given in this report. Recent trends in the use of licit and illicit drugs are emphasized, as well as trends in the levels of perceived risk and personal disapproval associated with each drug. This study has shown these beliefs and attitudes to be particularly important in explaining trends in use. In addition, trends in the perceived availability of each drug are presented. Following an introductory section are a synopsis of the methods used in the study and an overview of the key results from the 2005 survey. Next is a section for each individual drug class, providing figures that show trends in the overall proportions of students at each grade level: (1) using it; (2) seeing a "great risk" associated with its use; (3) disapproving its use; and (4) saying that they could get the drug "fairly easily" or "very easily." Trends for the interval 1991-2005 appear for all grades and for 1975-2005 for the 12th graders. The tables at the end of this report provide the statistics underlying the figures. In addition, they present data on lifetime, annual, 30-day, and (for selected drugs) daily prevalence. (Contains 13 tables.)