The potential between heavy quarks can be rigorously defined in a QCD effec
tive field theories framework. I discuss the general situation when the cou
pling constant may not be considered small and provide an explicit expressi
on for the potential valid up to order 1/m(2). Spin dependent and spin inde
pendent terms are expressed in terms of Wilson loops, completing land corre
cting) an ideal journey started twenty years ago with the classical work of
Eichten and Feinberg.