Results show that Quantifiler accurately predicted complete STR amplification failure (i.e., no alleles were amplified) after a single quantitation reading in 73 percent of “undetected” samples tested; however, given that one low-level “undetected” sample gave a full profile and several “undetected” samples yielded partial profiles, the data suggest that there is not an absolute true minimum value with the Quantifiler method using the ABI Prism 7000 Sequence Detection System. The study was purposefully based on a single quantitation attempt in order to reflect actual forensic laboratory practice. It should be noted, however, that samples whose quantitation values fall below the limit of detection for this method may give an inaccurate quantitation result that is not reproducible upon a second analysis. This could explain the occurrence of a full STR profile from an “undetected” sample, as well as the lack of any STR loci from several detected samples. Although an absolute minimum value for predicting STR success does not apparently exist for this method, the data developed suggest that most “undetected” samples from Quantifiler analysis will likely generate no profile or a partial profile that would likely contain so few typable loci that the information would not be useful for human identification purposes. The study obtained buccal swabs from each of 12 volunteers using sterile cotton swabs. Buccal swabs were chosen for the study because they are convenient, commonly used in human identity testing, and typically generate full STR profiles without having to adjust for PCR inhibition or degradation. The descriptions of materials and methods address DNA extractions, quantitation and dilution, STR amplification and capillary electrophoresis analysis, and data analysis. 1 table, 2 figures, and 17 references