This paper presents the results of a content analysis of alcohol and drug portrayals in the top 100 Billboard songs from each of the years 1968, 1978, 1988, 1998, and 2008, thus allowing both a characterization of substance portrayals in music generally and an analysis of changes over time. Of the final sample of 496 songs, 10.3% contained a reference to alcohol and 5.7% contained a reference to drugs. A substantial increase was found over the decades, and in particular over the last two: in 1988, 12% of songs referred to either or both classes of substance, compared to 30% in 2008. Marijuana was by far the most frequently mentioned drug. Both alcohol and drugs were much more likely to be portrayed positively than negatively, especially in recent decades. The results are discussed in terms of relevant theories of media processing and impact.