Nonperturbative corrections to moments of the decay B -> X(s)l(+)l(-) - art. no. 114028

We study nonperturbative corrections to the inclusive rare decay B -->X(s)l (+)l(-) by performing an operator product expansion to O(1/m(b)(3)). The va lues of the matrix elements entering at this order are unknown and introduc e uncertainties into physical quantities. We study uncertainties introduced into the partially integrated rate, moments of the hadronic spectrum, as w ell as the forward-backward asymmetry. We find that for large dilepton inva riant mass q(2)>M-psi(2), these uncertainties are large. We also assess the possibility of extracting the HQET parameters lambda (1) and <(<Lambda>)ov er bar> using data from this process.