The near-infrared absorption and FT-Raman spectra, taken with a near-infrared Nd:YAG source, were measured for two novel lanthanide ionomer systems. These ionomers are lanthanide exchanged copolymers based on two types of acid copolymer. One is organic and includes ethylene copolymers with acrylic or methacrylic acid; the other is inorganic and consists of carboxylated polysiloxane copolymers. The FT-Raman spectra of these systems differ greatly. Those based on organic copolymers exhibit strong lanthanide absorption frequency-dependent fluorescence, while those based on carboxylated polysiloxane do not. This difference is discussed in terms of the extent of lanthanide ion association in the ionomers.