Abstract: Prestressed composite tension members comprise an assembly which includes compression and tension portions which are loaded longitudinally along or symmetrical with the center of gravity of the compression portion and prestressed causing both the tension and compression portions to cooperate in resisting lengthening of the assembly rather than the tension portion alone, thus lessening such elongations. In one embodiment, the tension member forms a tension member in a truss, having an upper chord and vertical webs acting in compression, and the tension member comprises a tensioned cable mounted within a series of abutting, slotted and glued wood members under compression. In another embodiment, the tension member comprises a tensioned cable centered in a plurality of tubes in compression, forming the truss lower chord.