I examine the behavior of rare and other frequency adjectives in the tough-construction (TC). Due to the effects of a heretofore overlooked semantic selectional restriction, such adjectives have not generally been recognized as grammatical in the TC. I show here that they do occur grammatically in this construction when the relevant selectional restriction is satisfied. Specifically, as it does in non-TC sentences, rare in the TC requires that its subject be kind-denoting, a requirement not imposed on the embedded-clause gap position whose reference the TC matrix subject controls. In this, TCs with rare exemplify a previously unattested selectional and thematic asymmetry in the construction. On their face, the facts appear to argue strongly in favor of treating the rare-TC matrix subject as a thematic argument of the TC matrix predicate, an intriguing and challenging prospect given the fact that such an analysis has been roundly (though not universally) rejected for canonical TCs. Instead, I take the prima facie counterintuitive position that the rare-TC matrix subject is not a thematic argument of the TC matrix predicate; I argue that rare-TCs are thematically and syntactically identical to canonical TCs in this respect. I propose that the kind-denotation requirement for rare-TC matrix subjects is imposed indirectly, through the interaction of a selectional restriction on the infinitival argument of rare and the Agree calculus (Chomsky 2000, 2001) that identifies the TC matrix subject with the embedded gap position whose reference it controls (Rezac 2004, 2006). Beyond its contribution to our theoretical understanding of the perennially thorny TC, the present study constitutes, to the best of my knowledge, the first detailed empirical investigation of the behavior of adjectives like rare in the TC.