Trust-based　solutions　provide　some　form　of　payment　to　peers　to　encourage　good　behavior.　The　problem　with　trust　management　systems　is　that　they　require　prior　knowledge　to　work.　In　other　words,　peers　are　vulnerable　to　attack　if　they　do　not　have　knowledge　or　correct　knowledge　of　other　peers　in　a　trust　management　system.　Therefore,　considering　only　trust　is　inadequate　when　a　decision　is　made　to　identify　the　best　set　of　peers　to　utilize.　In　order　to　solve　the　problem,　we　propose　a　distributed　decision-making　mechanism　for　wireless　peer-to-peer　(P2P)　networks　based　on　game　theory　and　relevant　trust　mechanisms　in　which　we　incorporate　the　element　of　trust　and　risk　into　a　single　model.　The　main　idea　of　our　mechanism　is　to　use　utility　function　to　express　the　relationship　between　benefits　and　costs　of　peers,　and　then　make　the　decision　based　on　expected　utility　as　well　as　risk　attitude　in　a　fully　distributed　fashion.　The　unique　feature　of　our　mechanism　is　that　it　not　only　helps　a　peer　to　select　its　partners,　but　also　mitigates　vulnerabilities　in　trust-based　mechanisms.　Through　analysis　and　experiments,　we　believe　our　approach　is　useful　for　peers　to　make　the　decision　regarding　who　to　interact　with.　In　addition,　it　is　also　a　good　starting　point　for　exploring　tradeoffs　among　risk,　trust　and　utility.