<p>The Lorentz transformations may be derived based on the Principle of Relativity and a few other plausible physical assumptions, without introducing the Principle of the Constancy of the Velocity of Light. All existing derivations of this kind introduce a (pre-) causality (or equivalent) condition in order to constrain the transformations of coordinates to assume the form of the Lorentz transformations (or their Galilean limit). We show how such a condition may be dropped: as a consequence, the Principle of Relativity in itself implies any causal relationship to be conserved under a change of reference frame.</p>