This article describes the experience and outcomes of the National Institute on Drug Abuse–funded Criminal Justice Drug Abuse Treatment Studies 2 Improving Best Practices in Assessment and Case Planning for Offenders protocol in the state of New Jersey. The protocol was designed to test the effectiveness of an Organizational Process Improvement Intervention in improving four assessment and case planning domains for drug-involved offenders in correctional settings transferring to community treatment based agencies. This article describes the protocol and the change team model process through which correctional and community agency staff collaborated to improve assessment and case planning for offenders with substance abuse problems. The primary goal of these collaborative efforts was to link information across stages of the treatment continuum to improve service coordination. Data taken from qualitative interviews with agency participants are used to illustrate the common themes that emerged relating to the intervention process, barriers to implementing developed goals, and facilitative factors that contributed to successes. The findings from the current study provide indication that organizational process improvement strategies can be implemented within a correctional setting to reduce interorganizational barriers and to facilitate improvements in the continuum of care involved in the treatment of offenders with histories of substance abuse.