We give a path integral derivation of the annulus diagram in a supersymmetr
ic theory of open and closed strings with D-branes. We compute the pair cor
relation function of Wilson loops in the generic weakly coupled supersymmet
ric flat spacetime background with D-branes. We obtain a -u(4)/r(9) potenti
al between heavy nonrelativistic sources in a supersymmetric gauge theory a
t short distances.