This paper assesses the use of single nucleotide polymorphisms (SNPs) for forensic analysis. It demonstrates that relatively small arrays of approx. 50 loci are comparable to existing short tandem repeat (STR) multiplexes. A quantitative test, however, is a prerequisite for mixture interpretation. In addition, as the mixture proportion becomes low, it will be necessary to distinguish between the allele and background. Relatively small biallelic arrays are also suitable to distinguish between closely related individuals such as brothers.