The Council of Europe’s European Sourcebook of Crime and Criminal Justice Statistics assembled crime data for 36 European countries in the years 1990 to 1996. Crime trends differed from those in the United States. Drug and violent offenses particularly continued to increase until the end of the period. These trends are not easy to explain. One possibility is that mass migration throughout Europe during the last decade may have exacerbated all kinds of ethnic and social tensions. The article examines, and dismisses, other explanations, such as: “grand” sociological perspectives; explanations based on changing patterns of drug use; “zero tolerance” and explanations based on the response to crime. Most of the theoretical explanations of crime trends currently in vogue in the United States seem of little help in understanding current European trends. Generally, the most valid approaches seem to be routine activities and situational explanations. Figures. notes, table, appendix, references