  We generalize the classical notion of packing a set by balls with identical
radii to the case where the radii may be different. The largest number of such
balls that fit inside the set without overlapping is called its {\em
non-uniform packing number}. We show that the non-uniform packing number can be
upper-bounded in terms of the {\em average} radius of the balls, resulting in
bounds of the familiar classical form.
