The implementation of convicted felon DNA databases by increasing numbers of forensic science laboratories has created the need for a quick, efficient, and cost-effective method for isolating DNA from liquid blood samples. Because of the large number of samples involved, the ideal method would combine high throughput capability with maximal yield, high quality, and minimal time. This study found that the QIAGEN QIAamp Blood Kit/Tissue Kit satisfies all of those requirements. It is a simple, low-cost spin column procedure that yields purified DNA of approximately 20-30 kb that can be used directly in PCR or other enzymatic reactions without further purification. In comparison with the standard SDS-Proteinase K/organic extraction/microcon purification process used by many forensic laboratories, the QIAamp procedure consistently gave a two- to four-fold increased yield. The DNA obtained was of high molecular weight, showed little degradation, and was suitable for RFLP and PCR analyses. Figures, table, references