These data are part of NACJD's Fast Track Release and are distributed as they were received from the data depositor. The files have been zipped by NACJD for release, but not checked or processed except for the removal of direct identifiers. Users should refer to the accompanying readme file for a brief description of the files available with this collection and consult the investigator(s) if further information is needed. This study represents the first comprehensive national assessment of law enforcement uses of and perspectives on sex offender registration and notification (SORN) systems. The two-year, mixed-method study featured collection and analysis of interview data from over two-dozen jurisdictions, and administration of a nationwide survey of law enforcement professionals. The study examined ways in which law enforcement leaders, uniformed staff, and civilian staff engaged in SORN-related duties perceive SORN's roles and functions, general effectiveness, and informational utility. Additionally, the study elicited law enforcement perspectives related to promising SORN and related sex offender management practices, perceived barriers and challenges to effectiveness, and policy reform priorities. This collection includes two SPSS data files and one SPSS syntax file: "LE Qualitative Data.sav" with 55 variables and 101 cases, "LE Quantitative Data-ICPSR.sav" with 201 variables and 1402 cases and "LE Quantitative Data Syntax.sps". Qualitative data from interviews conducted with law enorcement professionals are not available at this time.