The preparation and operation of a chromium electrodeless discharge lamp and its use in studying the atomic fluorescence characteristics of chromium in an argon-separated air-acetylene flame are described. A detection limit of 0.005 p.p.m. for the combined fluorescence at 357.9 nm, 359.4 nm and 360.5 nm is obtained. Of 38 elements examined for interference in 250-fold amounts (by weight) in the fuel-lean separated flame, only three (Ce, Si and Ti) produce a slight positive interference of 4–6%. Many more elements interfere in the thermal emission of chromium at 425.4 nm, 427.5 nm and 428.9 nm which in combination gives a detection limit of 0.02 p.p.m. on the same apparatus.