In planning an undercover operation, strategies should be developed on the basis of available evidence and the evidence needed. The cover should be realistic and should be conducted in accordance with the Attorney General's guidelines for Federal Bureau of Investigation undercover operations. A risk analysis should weigh the costs and benefits of the operation to the agent, the subject, and the general public. The Federal prosecutor should be an active participant in the operation, assisting in planning of strategies and tactics, review of evidence custody and control procedures, and continuing reassessment of the operation. Evidence in public corruption cases most often is obtained through consensual recordings of the agents' or informants' conversations and activities. Informants can be indispensable in obtaining detailed intelligence and establishing contacts for the undercover agent, but they must be carefully managed and controlled. Special considerations apply in cases involving bribery or other corruption in the courts and legislatures. If the undercover operation fails to produce the needed evidence, the use of search warrants, electronic surveillance, or other investigative techniques is advisable.