The measurements of the mass of the W boson (M_W) and of the top
quark (M_t) are important for three reasons: (i) these masses represent
fundamental parameters of the Standard Model; (ii) they determine the
coupling between the top quark and the Higgs boson, the coupling being
proportional to M2_t/M2_W; and (iii) radiative corrections relate the
masses of the W, top quark and the Higgs boson: an accurate measurement of
M_W and M_t would provide a constraint on the Higgs mass (M_H).