We present a set of global
invariants, called “mass integrals", which can be defined for a large class of
asymptotically hyperbolic Riemannian manifolds. When the “boundary at infinity"
has spherical topology one single invariant is obtained, called the mass; we show
positivity thereof. We apply the definition to conformally compactifiable manifolds,
and show that the mass is completion-independent. We also prove the result, closely
related to the problem at hand, that conformal completions of conformally
compactifiable manifolds are unique.