This study is of forensic interest because dog and cat hairs pervade the homes, cars, and clothing of pet owners and are readily transferred to and from crime scenes. Animal hairs can be analyzed with techniques similar to those used for human hairs. Summary statistics for number of alleles, expected and observed heterozygosity, and power of exclusion are compared between breeds. The authors advise that marked population substructure in dog breeds indicates significant inbreeding, and the use of a conservative theta value is recommended in likelihood calculation for determining the significance of a DNA match. This study presents evidence that the informativeness of the canine microsatellites, despite inbreeding, is comparable to the human CODIS loci. Two case studies that used canine DNA typing are described: State of Washington v. Kenneth Leuluaialii and George Tuilefano, as well as Crown v. Daniel McGowan. In these two cases the identification of individual dogs, using bloodstains and hairs, established links between victims and suspects. For ease of analysis, the Stockmarks for Dogs Canine 1 kit is a commercially available, quality-controlled PCR multiplex that includes one trinucleotide locus and nine tetranucleotide loci. Another PCR multiplex that consists of seven additional tetranucleotide loci provides additional power for identification in forensic cases. 8 tables, 5 figures, and 37 references