  We propose a method to improve lattice operators composed of Wilson fermions
which allows the removal of all corrections of $O(a)$, including those
proportional to the quark mass, leaving only errors of $O(a^2)$. The method
exploits the fact that chiral symmetry is restored at short distances. By
imposing this requirement on correlation functions of improved lattice
operators at short distances, the coefficients which appear in these operators
can be determined. The method is an extension of the improvement program of the
ALPHA collaboration, which, up to now, has only been applicable in the chiral
limit. The extension to quarks with non-zero masses is particularly important
for applications in heavy quark physics.
