SciFi.com describes "Passage" as "an emotionally exhausting trip" that is ultimately "a rewarding experience." Laura Miller, writing for "Salon", says that "its construction is a marvel of ingenuity and — what's even more remarkable, given the wizardry of Willis' storytelling — its intellectual honesty is impeccable... You won't find the beautiful sentences of more-celebrated 'novelists of ideas' here, though the ideas themselves are far better, more daring and more original, than those chewed over by most literary heavyweights. The dialogue can sound a trifle canned, the minor characters feel a mite thin (not that many novels of ideas don't share these flaws, too), which explains in part why "Passage" seems to hover between genre and genius. Given how rare a searching intelligence like Willis' is among today's novelists, does it really matter?"