The grand jury's development into a cutting investigative edge for prosecutors is a natural outgrowth of its procedural and institutional framework. In most Federal and State investigations, a grand jury subpoena is the only process by which pretrial testimony can be compelled, and the grand jury is the only forum for receipt of statutorially immunized testimony. The utility of the grand jury to the prosecutor is heightened by the milieu in which it operates. The proceedings are secret; there are few limitations on the scope of questioning; witnesses have no right to the presence of counsel in the grand jury room; and evidence that would be inadmissible in other legal forums is routinely adduced from the witness. Counsel's first task when confronted with a subpoenaed client is to determine whether the client is a target of the investigation through a preliminary discussion with the prosecutor, if he or she is willing to discuss the matter. If the client is an active or potential target of the investigation, or if the information in the client's possession is potentially incriminating, counsel should attempt to convince the prosecutor that the witness's testimony is available only in return for a grant of immunity. Without such immunity, and absent extraordinary circumstances occasionally encountered in white-collar investigations, the witness should be advised to invoke the fifth amendment privilege against compulsory self-incrimination. The article concludes with an outline of some proposed standards for grand jury reform.