In this paper, we show that it is not a conceptual truth about laws of nature that they are immutable (though we are happy to leave it as an open empirical question whether they do actually change once in a while). In order to do so, we survey three popular accounts of lawhood—(Armstrong-style) necessitarianism, (Bird-style) dispositionalism and (Lewis-style) ‘best system analysis’—and expose the extent, as well as the philosophical cost, of the amendments that should be enforced in order to leave (...) room for the possibility of changing laws. (shrink)