Abstract : A theoretical and analytical analysis is presented on the application of multispectral emission/absorption inversion to the retrieval of temperature and concentration profiles of tactical rocket motor plumes. Consideration is given to both monochromatic and band model spectral scales. A main conclusion drawn from the analysis is that application in the infrared on either the monochromatic or wide band spectral scale cannot yield adequate inversions for small plumes with mild temperature gradients such as those encountered for tactical rocket motor. Even under the most ideal circumstances, temperature and concentration errors up to 30% are encountered. The failing of the method is due to the lack of spatial resolution inherent in the inversion weighting functions.