By using angle-resolved photoemission with synchrotron radiation, we have determined accurate energy-versus-momentum dispersion relations along symmetry lines \ensuremath{\Gamma}X and \ensuremath{\Gamma}KX for lead crystals. These directions are mapped out by recording normal-emission photoelectron spectra at low temperatures (20 K) from Pb(100) and Pb(110) surfaces, and by interpreting the experimental data in terms of the direct-transition model. However, in the photon-energy range 55--65 eV the photoemission curves for Pb(100) are best interpreted by taking into account the influence of inelastic electron scattering in the final state (momentum-nonconserving transitions). The experimental dispersion curves for the valence bands of p and s symmetry are in fine agreement with the theoretical electronic structure obtained by relativistic augmented--plane-wave (APW) and linear rigorous cellular (LRC) methods.