Once a determination is made that an internal investigation is necessary, the company must develop an investigative plan.  The resulting work plan should be flexible, but also concretely define the scope of the investigation, including:  the time period to be reviewed; a description of the document sources to be evaluated, such as email accounts for likely custodians or certain company accounting records; a process for reviewing collected materials, including whether search terms will be used to cull data; and whether interviews will be conducted.  The work plan should also include an estimated timeline for the investigation and a proposed method for reporting the investigatory findings.  The timing of the investigation may be crucial if the company is facing a potential government investigation.  When drafting a work plan, it is important to keep in mind the nature of the questions to be answered by the investigation.