The primary investigators of procurement fraud are inspectors general in a number of civilian agencies, the Defense Procurement Fraud Unit within the Department of Justice (DOJ), and the Defense Contract Audit Agency. The most significant criminal offenses that may arise in the procurement context are false statements, false claims, mail or wire fraud, conspiracy to defraud, bribery, illegal gratuities, or racketeering. Conviction for any of these criminal offenses carries the possibility of fines and imprisonment. Corporations as well as individuals may be held criminally liable. Recently, the DOJ and the inspectors general have targeted certain areas deemed most vulnerable to fraudulent conduct by prime or subcontractors. Among the most significant are defective pricing, mischarging, product substitution, and bid collusion. A grand jury must consider any criminal charges that may be brought against a contractor for procurement fraud, and upon conclusion of its investigation, either indict the contractor or refuse to do so. The grand jury may subpoena both documents and witnesses. Guidelines are outlined to alert contractors to some of the problems they may encounter in procurement fraud investigations and to help them in taking measures to prevent such problems. A list of 199 references is provided.