Composite　approaches　have　been　developed　in　lead-free　solder　research　in　an　effort　to　improve　the　service　temperature　capabilities　and　thermal　stability　of　the　solder　joints.　This　article　overviews　the　background　for　composite　lead-free　solder　development,　the　roles　of　reinforcements　and　their　requirements,　composite　solder　processing　techniques,　as　well　as　current　status　of　composite　solder　research.　Examples　of　several　representative　lead-free　composite　solders　produced　with　various　methods　and　reinforcement　types　are　presented.　The　effects　of　reinforcement　addition　on　processing　and　mechanical　properties　are　analyzed.　Difficulties　and　problems　that　exist　in　composite　solder　research　are　proposed　and　tentative　solutions　are　attempted　with　examples　of　newly　emerging　novel　lead-free　composite　solders.　©　2007　Springer　Science+Business　Media,　LLC.