In recent years, Conjugated polymers have been widely used as fluorescent chemosenors. The related sensing mechanism, energy migration along the polymer backbone, and some other aspects of these polymer sensors will be briefly explored. Conjugated polymer molecular wires are constituted by the polymer backbone and its receptors. We will describe two types of conjugated polymers that can be used as fluorescent chemosenors, showing either fluorescence “turn-on” or “turn-off” effects when binding cations. This is accomplished by assembling different ligands onto the polymer backbone. Conjugated polymer molecular wires have advantages over small molecules for sensing applications due to enhancements associated with electronic communication along the polymer backbone and increased selectivity through the use of different receptors. Here we present recent advances in the synthesis of conjugated polymers with varying conjugation and receptors along the polymer backbone.