The discovery and synthesis of fullerenes led to the hypothesis that fullerene compounds may be present and stable in interstellar space. As first evidence for the largest molecule ever detected in space, we have recently detected two new diffuse interstellar bands (DIBs) that are consistent with laboratory measurements of the C60 cation. From these observations we estimate that up to 0.9 % of interstellar carbon could be in the form of C60+. This suggests that fullerenes may play an important role in interstellar chemistry. We propose to observe with ISO SWS the vibrational transitions of the fullerene C60 (neutral, cation and anion), as well as the transitions of exohedral fullerene compounds formed with H or metals such as Na, K. The wavelength positions and oscillator strengths of these transitions are derived from recent laboratory measurements in Ne matrices. Fullerene compounds may be present as neutral and ionized species in the diffuse interstellar medium and dominantly neutral in dense clouds. We intend to observe extincted targets in the diffuse interstellar medium, embedded protostars in dense molecular clouds and potential progenitor sources (C stars). These observations will provide the abundances of fullerenes species in lines of sight for which visible diffuse interstellar bands, attributed to the C60 cation, have been measured. The general aim of this proposal is to contrain the production, stability and role of fullerenes in interstellar chemistry.