LPD　communication　has　recently　emerged　as　a　new　transmission　technology　to　address　privacy　and　security　in　wireless　networks.　Recent　studies　have　established　the　fundamental　limits　of　LPD　communication　in　terms　of　the　amount　of　information　that　can　be　conveyed　from　a　transmitter　to　a　receiver　subject　to　a　constraint　on　a　warden＇s　detection　error　probability.　The　established　information-theoretic　metric　enables　analytical　studies　on　the　design　and　performance　of　LPD　communication　under　various　channel　conditions.　In　this　article,　we　present　the　key　features　of　LPD　communication　and　discuss　various　important　design　considerations.　First,　we　clarify　the　differences　between　LPD　communication　and　well-known　physical-layer　security.　Then,　from　an　information-theoretic　point　of　view,　we　discuss　the　optimal　signaling　strategies　for　transmitting　the　message-carrying　signal　and　artificial　noise　signal　for　LPD　communication.　Finally,　we　identify　the　key　challenges　in　the　design　of　practical　LPD　communication　systems　and　point　out　future　research　directions　in　this　context.　This　article　provides　guidelines　for　designing　practical　LPD　communication　strategies　in　wireless　systems　and　networks.　©　2002-2012　IEEE.