This report is part of the Youth Crime Gun Interdiction Initiative, a 17-city demonstration project aimed at reducing youth firearms violence. For the purpose of this project, a "crime gun" is defined as "any firearm that is illegally possessed, used in a crime, or suspected by enforcement officials of being used in a crime." As part of providing crime gun trace information for a 10-month period, this report contains analyses of requests for crime gun traces; analyses of successful NTC traces; analysis of incomplete traces; and analyses by adult, youth, and juvenile age categories. For the study period, Seattle had 487 crime gun trace requests to the NTC; of these, 351 (72.07 percent) possessors were identified. A total of 336 requests involved the determination of the possessor's age; there were 159 adult (25 years of age and over) trace requests, 108 youth (18-24 years old) trace requests, and 69 juvenile (17 years old and under) trace requests. An analysis of trace requests by type of firearm shows that the semiautomatic pistol was the most frequently traced firearm for youth and juveniles: 70 for youth and 43 for juveniles. Rifle was the type of firearm most often traced for adults (n=62), followed closely by the semiautomatic pistol (n=57). Another table shows the top 10 crime guns requested for tracing by type, manufacturer, and caliber. Firearms offenses was the crime type most often associated with trace requests: 129 for adults, 86 for youth, and 53 for juveniles. The number of successful traces was 34 for adults, 46 for youth, 26 for juveniles, and 151 for all ages. Other data reported show time- to-crime rates for the top 10 crime guns requested for tracing by type, manufacturer, and caliber, as well as the most frequent source-State for successfully traced crime guns; the top State was Washington for all age categories. General findings are discussed for all the participating communities and for local illegal firearms markets.