In 2001, Portugal decriminalized the acquisition, possession, and use of small quantities of all psychoactive drugs. The significance of this legislation has been misunderstood. Decriminalization did not trigger dramatic changes in drug‐related behavior because, as an analysis of Portugal's predecriminalization laws and practices reveals, the reforms were more modest than suggested by the media attention they received. Portugal illustrates the shortcomings of before‐and‐after analysis because, as is often the case, the de jure legal change largely codified de facto practices. In the years before the law's passage, less than 1 percent of those incarcerated for a drug offense had been convicted of use. Surprisingly, the change in law regarding use appears associated with a marked reduction in drug trafficker sanctioning. While the number of arrests for trafficking changed little, the number of individuals convicted and imprisoned for trafficking since 2001 has fallen nearly 50 percent.