Fire investigation begins with the person receiving the call reporting the fire. The identity and address of the person reporting the fire should be determined as well as a description of the fire. The date, time, and the way in which the message was transmitted must also be recorded. En route to the fire scene, firefighters should look for unusual circumstances, such as persons or vehicles hurriedly leaving locations near the fire. In addition to performing the duties required to extinguish the fire and conduct rescue operations, the firefighter should observe any clues that arson may have been committed, such as covered windows and doors (to delay discovery), evidence of forcible entry, whether doors were open or locked, unusual odors, and obstacles placed to hinder firefighting. Also, the absence of property that might be expected in the building or home may be evidence of premeditated arson by the owner. Other indicators of arson would be charring in unusual places located away from any accidental ignition sources, the speed of the fire spread, and evidence of tampering with fire suppression devices and equipment. Spectators at the scene should also be observed for any unusual behavior. Once the officer in charge determines that a fire is suspicious, the police should be called in, along with a State fire marshal inspector, or, ideally, the arson investigation squad. The most effective and efficient investigations result from cooperation and an understanding of the roles and expertise of each involved agency. Throughout the investigation, it is essential that documentation in the form of notetaking, preservation of physical evidence, and photography be meticulously complete and controlled. Investigators' skills in identifying evidence at the fire scene and in interviewing witnesses depend upon proper training. The Massachusetts Fire Academy staff working in conjunction with the State Police Academy, offers an 80-hour course that provides the knowledge required for effective arson investigations. The program culminates in an actual fire investigated by a student team whose results are presented in a simulated courtroom presentation.