The author discusses the LSD (Least Squares Deconvolution) objective mathematical approach to interpreting two-person mixtures, as well as the Combined Probability of Inclusion/Probability of Exclusion method. The guidelines recommend separating mixed DNA profiles into six specific types, which simplifies the process of identifying individual contributors. One type consists of a set of two mixed DNA profiles that contain a male and a female contributor, specifically a sperm (male) and an epithelial (female or nonsperm). The second mixture type is a mixed DNA profile obtained from a single sampling of a specimen (usually nonsemen-related), to which a forensically valid assumption can be applied. The third type of mixture has a distinct major contributor and a trace minor contributor, and the fourth type of mixture is a mixed profile with one major contributor and one minor contributor. The fifth mixture type is a mixed profile with one major contributor and more than one minor contributor. The sixth type of mixture is a mixed profile with no distinct major and/or minor contributors. The separation of mixed DNA profiles into distinct types retains significant case-specific information by considering relevant known DNA profiles. If a forensically valid assumption can be made regarding the presence of a contributor expected to be present, then consideration of the contribution of a known sample can be used in deducing another contributor. If no assumptions can be made based on case-specific knowledge, a more conservative interpretive approach is warranted. Where appropriate, indication of a sole source may be possible. 8 figures, 2 tables, and 34 references