Investigating officers must somehow establish, document, and preserve the reality that surrounds some specific event. Social networks form a background to almost every event and include the family, neighbors, friends, and others. Individuals also have ethnic, cultural, and community networks; business, professional, and occupational relationships; political ideologies; and other personal and emotional affiliations. When conducting an interview, the police officer must first focus on the elements of the offense, the physical facts and occurrences, the sequence, legal issues, and the investigative status of the person being interviewed. Networks have secondary and varying importance to particular investigations. Police should keep informed about a community's networks. In an interview, using unstructured inquiry is the first step toward identifying networks. The interview may provide information that will be useful in subsequent interviews. Making a written diagram may be helpful to clarify the relationships involved. 3 references