HQET and Inclusive Decays of Heavy Hadrons

We discuss the recent developments in inclusive decays of hadrons containing a heavy quark. The subject is approached in a model independent way using an operator product expansion for the time-ordered product of weak currents. We discuss the extraction of the weak mixing angle $|V_{cb}|$ from inclusive semileptonic $B$ decays and the application of these techniques to the endpoint of the $e^-$ spectrum in $B\rightarrow X_ue\nu$. We also suggest that the comparison of inclusive semileptonic widths for $D_s$ and $D$ mesons will give an indication of the consistency of this approach in charm decays. \bigskip {\it Invited talk presented at the "Intersections of Particle and Nuclear Physics" conference, St Petersburg, Florida, 31 May to 6 June, 1994.}