I will present an overview of inclusive b meson measurements at CLEO that are used to improve our knowledge of the CKM matrix. Specifically, I will describe the measurement of the moments of various spectra.  These measurements are used to constrain the values of non-perturbative Heavy Quark Expansion parameters, L and  l₁ .  The constraints allow a more precise determination of V_cb. I will also present similar advances in the extraction of V_ub.