Fluorescence emission spectra are recorded for Langmuir-Blodgett (LB) films prepared from cellulose derivatives containing carbazole as a sidechain substituent. Three samples of differing carbazole content are considered. At low carbazole content, only the fluorescence characteristic of monomeric carbazole emission is observed. Clear excimer emission is, however, evident in the spectra of the more highly substituted derivatives. Since similar excimer formation is not observed in solutions or cast films of the same polymers, it is concluded that molecular ordering in the LB films favours the parallel alignment of chromophore units. For a given polymer of sufficiently high carbazole content, the relative intensity of the excimer emission increases with the number of transferred layers, indicating the interaction of chromophores in neighbouring layers. Energy transfer between layers is also evident in experiments involving multilayer assemblies composed of a monolayer of 1-pyrenedodecanoic acid, covered with a varying number of layers of the carbazole-containing polymer; Excitation of carbazole results in strong emission from pyrene, whereas only weak emission is observed from carbazole. Ii is therefore concluded that energy transfer from carbazole to pyrene occurs in these LB films.