The present chapter describes the synthetic strategies used for the preparation of electroluminescent conjugated polymers via metal catalyzed coupling reactions. Synthesis of these polymeric materials having complex macromolecular architectures, composition or functionalities involves the use of several controlled polymerization methods, namely Atom Transfer Radical Polymerization (ATRP) and Ring Opening Polymerization (ROP). Essentially, new functional compounds as initiators in the above-mentioned methods, were designed, synthesized and used to obtain different types of telechelics or macromonomers. New poly(p-phenylene) (PP) and poly(p-phenylene vinylene) (PPV) derivatives bearing macromolecular side chains were readily synthesized by cross-coupling processes (Suzuki or Yamamoto coupling) or/and Wittig reaction of appropriate combination of these well-defined macromolecules. The final soluble and processable conjugated polymers could find applications as high technology materials due to their properties such as conductivity and luminescence.