pi-Conjugated molecules are interesting components to prepare fluorescent nanoparticles. From the use if polymer chains that form small aggregates in water to the self-assembly of small chromophoric segments into highly ordered structures, the preparation of these materials alllows to develop systems with application as sensors or biolabels. The potential functionalization of the nanoparticles can lead to specific probing. this progress report describes the recent advances in the preparation of such emittive organic.