The literature on generational differences in crime and victimization in the United States and Western Europe reveals striking variations in patterns within and across racial and ethnic groups. By the turn of the twentieth century, scholars had already begun to disaggregate offending patterns across immigrant generations. Findings can be disaggregated by crime (e.g., homicide, violent crime, delinquency, and substance abuse) and types of victimization (e.g., nonfatal and fatal). Among the challenges in measuring generational differences in crime among immigrant populations are a shortage of available data that accounts for generational status, definitional issues with key terms such as “immigrant” and “native-born,” and both the need to and difficulties in disaggregating data by race, ethnicity, and types of crime.