 (6) The popular conception of sexual orientation is not so crude as to rely solely on behavior, but it is silent on what we should rely. Desires and fantasies are obvious candidates. But occurrent desires are not a good guide to sexual orientation: a shepherd can sexually desire sex with a sheep, but he need not be a zoophile, even were his desire for it to recur. David—a straight guy—might desire oral sex from another man (Tom) or other men. Recourse to “enduring desires”, as in the APA’s definition, might not do the trick if the conditions under which David desires oral sex from other men recur. Other information, such as counter-factual information as to what the person would do under such-and-such conditions (e.g., Stein’s “ideal conditions”; 1999: ch. 2), is needed—if David prefers a woman’s mouth under ideal conditions, then he is straight. But stating these conditions is tough. What if David prefers the way that Tom performs oral sex? David might, under some conditions, still opt for Tom (Corvino 2006a; cf. Díaz-León, forthcoming).