The only way to effectively secure radio communications is to encrypt the voice message from the mouth of one officer to the ears of others. This requires the use of voice scramblers and the first step toward procurement is to determine the requirements of the particular organization. Important criteria for considering a voice security system include security level, system transparency, voice quality and recognition, and ease of operation. Small police departments need a scrambler that uses a simple encoding method to deter casual listeners operating a scanner. In urban areas, digital time division encryption achieves the purpose of securing voice transmissions to a point where they are virtually unbreakable in tactical real-time.