In this chapter, after briefly reporting on GRBM in-flight performances and operational status and describing the in-orbit background level and properties, we outline the techniques for the application of the ratemeters and spectra response functions described in chapter 3 to the estimate of flux, spectral evolution and average spectral properties of high energy transients, in particular Gamma-Ray Burst. We also show how we can derive flux and spectrum of bright hard sources by exploiting their occultation by the Earth and how this technique has been applied to obtain the Crab nebula fluxes in the GRBM and ratemeters band and the 240-channel spectrum, allowing in-flight verification of LS1 and LS3 response functions. Finally, we describe joint GRBM + WFC data analysis methods and the cross-calibration of the two instruments.