This entertaining two-gallery exhibition introduces 14 Europeans who make high-concept works in nontraditional media. The title ''OK/Okay'' alludes to the uncertain etymology of the word, to suggest how slippery words and their meanings can be.

Most works in the show have the amusing legibility of one-liners. Gabriele Di Matteo's series of small paintings, ''History Stripped Bare,'' depicts hundreds of historical scenes in which the characters -- from Neanderthal man to Condoleezza Rice -- are represented nude. In Werner Reiterer's ''Beginning of Space Travel,'' a hose from a compressed-gas tank connects to a stuffed cat that hangs from the ceiling as though floating like a balloon. And Leopold Kessler's ''Ejecting Fridge'' pops open and spills out food products when you step on a nearby floorboard.

Christian Andersson has a paragraph from a science-fiction story about the molecular dematerialization of reality projected onto a wall, on the other side of which the glowing letters reappear in reverse as though the wall were dematerializing. For his installation, Nedko Solakov has arranged actual artworks from the Grey Art Gallery's collection -- including a de Kooning and some Warhols -- in and about the simulated hut of a fictional African native who collects European and American art.

Graham Gussin's performance piece ''Transitory,'' involves a person walking back and forth between the Swiss Institute and the Grey Art Gallery on Saturdays from 11 a.m. to 5 p.m. and at ''other undesignated times during the week.''