There is surprisingly little philosophical work on conceptually spelling out the difference between the traits on which natural selection may be said to act (e.g. “having a high running speed”) and mere circumstantial traits (e.g. “happening to be in the path of a forest fire”). I label this issue the “selectable traits problem” and, in this paper, I propose a solution for it. I first show that, contrary to our first intuition, simply equating selectable traits with heritable ones is not (...) an adequate solution. I then go on to argue that two recent philosophical solutions to this problem—due to Peter Godfrey-Smith and Pierrick Bourrat—are unconvincing because they cannot accommodate frequency-dependent selection. The way out of this difficulty is, I argue, to accept that extrinsic properties dependent on relations between intrinsic properties of the population members should also count as selectable traits. I then show that my proposal is legitimized by more than the simple accommodation of frequency-dependent selection. (shrink)