We study the assemblies that tetra(carbomethoxy)tetrathiafulvalene (TCM-TTF) forms in solution and when deposited on a surface depending on intermolecular interactions and on the interactions with the substrate and the solvent. Its organization on graphite and mica substrates was studied by atomic force microscopy, and different molecular assemblies were observed depending on the prevailing interactions. The promotion of molecule-molecule interactions gave rise to the formation of molecular fibers. The investigation of the influence of the solvent-molecule interactions on TCM-TTF molecular organizations was carried out by UV/Vis spectroscopy, and a new TCM-TTF polymorph was obtained by changing the nature of the solvent. Finally, an explanation for all these phenomena, supported by computational modeling, is put forward.