The study found that prosecutors in large offices in metropolitan areas with multiple targets at high-risk for terrorist attacks had a more significant role in identifying and prosecuting precursor crimes than smaller offices in cities with fewer high-risk targets. The antiterrorism focus of the prosecutors in large urban areas included the disruption of precursor terrorist activity through initial identification and information-sharing with Federal prosecutors, along with the local prosecutors of the precursor crimes. Case studies show that the identification and prosecution of precursor crime actually related to terrorism requires prosecutors to rethink how routine criminal behavior may be linked with terrorism and which characteristics of both offenses and offenders may indicate a link to plans for a significant terrorist attack. The role of a well-informed local prosecutor in supporting the Federal response to terrorism is clearly helpful, whether through information-sharing, collaboration on investigations, or in prosecuting precursor crimes committed in their jurisdictions. Out of the 112 prosecutors' offices selected for the study, 70 responded to the survey (62.5-percent response rate). Survey questions were designed to determine the extent to which prosecutors had used their States' antiterrorism legislation, whether or not they had prosecuted any precursor crimes related to terrorism, and how they coordinated their efforts with those of Federal prosecutors. Five offices were selected for intensive case study. 1 figure and 19 references