“The Principles report outlines ten operating guidelines that define highly-successful system-level responses to address the needs of drug involved individuals. And the needs are staggering – with estimates as high as 60 percent of arrestees in jail with positive drug tests and fragmented service networks in the highest need communities, the responsibility to treat and rehabilitate drug-involved defendants and offenders has fallen squarely on criminal justice systems. While some systems have had notable successes in meeting these challenges, others continue to struggle. Principles provides a roadmap for leaders and practitioners with guidance like how to identify how severe the substance use is among defendants and offenders, address the diagnosed drivers contributing to the substance abusing behavior, and how to determine the level of intervention based on severity of substance use and on risk to reoffend.” This publication contains sections about: the ten principles of an effective criminal justice response; risk, needs, and evidence-based responses; and moving from aspirational to operational.