Since its introduction, polymerase chain reaction (PCR) has become a widely used, routine technique in forensic laboratories. However, a number of PCR protocols are being replaced by more powerful approaches, particularly those based on multiplex amplification of short tandem repeat (STR) loci. One alternative form of multiplex PCR amplification, called Sequential Multiplex Amplification (SMA), was designed to amplify a single locus and then recover and reuse the remaining genomic DNA as a template for subsequent PCR. The SMA process could be repeated several times. SMA has proven useful in typing genomic DNA contained in stored PCR samples and analyzing samples of limited quality or quantity for multiple loci. The efficacy of the use of SMA for actual typing of casework samples permitted typing for a second locus 98.11 percent of the samples considered; 70.75 percent were typeable for a third locus, and 16.98 percent for a fourth locus. Tables, references