When a series of sexual assaults has been committed by one person, it is important to recognize that the crimes are linked and to combine all the evidence to provide the maximum amount of information on the perpetrator. The Metropolitan Police Forensic Science Laboratory does this by providing a form on each case which records details of the crime. It also obtains data from the sexual assault data checklist in the sexual offenses kit, the victim's statement, the investigating officer's statement, and laboratory results. Information on the victim encompasses sex and age, and information on the offender includes ethnic appearance, age, physical description, personal peculiarities, type of weapon (if used), and vehicle description (if used). Information on the crime involves the type of sexual assault, offense location, approach to victim, method of attack, and scientific results. If a computerized search of the sexual assault index suggests a series of offenses committed by the same person, a list of the cases is sent to Crime Pattern Analysis and to the detective chief superintendent of the area involved. A chart showing the linked cases is also prepared at the laboratory, showing details of the modus operandi, descriptions of the offenders, semen grouping results, and any other laboratory findings. 2 tables and 1 reference.