This paper provides a descriptive and comprehensive account of the transformations in the Portuguese juvenile justice system and in the state’s reactions to youth delinquency after the 1999 legal reform. The empirical data do not show an increase in the criminalization of youth, as could be expected by the shift from a “protection” model toward a responsibilization model. The interpretation of the reported trends in light of the influence of “global criminalization factors” (the developments of welfare policies, human rights, victims, and public opinion/media) at work in the case of Portuguese suggests that these factors should be considered in connection with larger historical, political, social, and cultural processes. In fact, the same factors do not produce the same effects everywhere.