The formulas E = mc2, m = m0(1 - v2/c2)-1/2 and E2 - p2c2 = m0(2)c4, widely known as ''(special) relativistic dynamics,'' follow quite naturally from the wave mechanics of de Broglie. The special relativistic kinematics (SRK) plays no significant role in quantum mechanics, which remains immune to possible inconsistencies in SRK.