  We evaluate matching conditions for the Wilson coefficients of operators
mediating the $b \to s \gamma$ and $b \to s gluon$ transitions in a large class
of extensions of the Standard Model. The calculation is performed at the
leading order in flavor-changing couplings and includes two-loop QCD
corrections. These corrections can be numerically important when approximate
cancellations occur among the new physics contributions and/or the SM one.
