This chapter deals with the analysis of complex DNA profiles. We have defined these as any mixed sample, whether or not one or more components are at low template levels. The analysis of forensic stains will inevitably lead to mixtures of DNA from different individuals, as a result of the mixing of body fluids and secretions. The recognition, resolution and statistical evaluation of such mixtures are therefore integral and vital parts of forensic casework. The subject is relatively complex and requires experience and judgement. It is often treated as a separate competency by forensic organizations. Often scientists move to mixture interpretation after experience with simple stains. It is desirable that a formal training and testing programme be associated with this transition.