The morphology of poly(N-cyanoethylpyrrole) has beencontrolled through the polymerization process. This polymer has beenprepared by anodic polymerization, chemical oxidative polymerization inemulsion medium, and layer-by-layer templating polymerization. Anodicpolymerization using LiClO4 as supporting electrolyte provides compactfilms, in which the oxidation degree is controlled through the thickness, usefulfor the microdetection of dopamine. Chemical polymerization using FeCl3 asoxidant agent results in very well-defined microspheres with porous internalstructure, which may be useful in molecular loading and transport processes.Finally, the layer-by-layer templating technique produces core−shell particlesof controlled size and thickness. Moreover, these core−shell particles can beeasily converted in hollow microspheres by removing the template