We obtain general results on the stability of rapid (superpolynomial)
decay of correlations for hyperbolic flows.
Let M be an n-dimensional
compact manifold, r>= 2n-1. Amongst the C^r Axiom A flows, there
is a C^{2n-1}-open, C^r-dense set of flows for which each
nontrivial hyperbolic basic set is rapid mixing.
For nontrivial attracting hyperbolic basic sets, we
obtain a C^1-open, C^r-dense set of rapid mixing flows, each r>=1.