Over several decades, Cora Diamond has articulated a distinctive way of thinking about ethics. Prompted by a recent critique of Diamond, we elucidate some of the main themes of her work, and reveal their power to reconfigure and deepen moral philosophy. In concluding, we suggest that Diamond’s moral philosophical practice can be seen as one plausible way of fleshing out what Wittgenstein might have meant by his dictum that “ethics is transcendental”.