The N-JOV Study collected information from a national sample of law enforcement agencies about the characteristics of Internet sex crimes against minors and the number of arrests for these crimes during a 1-year period. The goals of the study were to estimate a baseline number of arrests during a 1-year period, so that the increase in the number of these cases can be measured in the future; to develop a statistical portrait of the characteristics of Internet sex crimes against minors and how such cases are handled by the criminal justice system; and to organize the cases into a typology useful for tracking and analysis. The study found that law enforcement agencies at all levels made an estimated 2,577 arrests for Internet sex crimes against minors during the 12 months that began on July 1, 2000. The types of crimes for which arrests occurred were as follows: Internet-related contacts between offenders and victims that resulted in sexual assaults and the use of the victims in the production of child pornography (39 percent of arrests); Internet solicitations for sexual contact made to undercover law enforcement officers posing as minors (25 percent of arrests); and the possession, distribution, or trading of Internet child pornography by offenders who did not use the Internet to sexually exploit identified victims or solicit undercover investigators (36 percent of arrests). Two-thirds (67 percent) of offenders who committed any of the types of Internet sex crimes against minors possessed child pornography. The vast majority of offenders were non-Hispanic White males older than 25 who were acting alone. Most investigations (79 percent) involved more than one law enforcement agency. State, county, and local agencies were involved in 85 percent of all cases; Federal agencies were involved in 46 percent of the cases. Apparently there were fewer dismissals and acquittals in cases that involved Internet-related sex crimes against minors than for conventional prosecutions of child sexual abuse. 3 tables, 6 figures, and 5 references