Constraints on leptoquark masses and couplings from rare processes and unification

Motivated by the recent experimental H1 and ZEUS data at HERA, which have reported evidence for leptoquark production at s=314 GeV with a mass at mD = 200 GeV we consider their implications in unified supersymmetric theories. We also present calculations for leptoquark production incorporating the existing limits from other exotic reactions on its couplings and other relevant parameters.