Some fashion industry and art world alliances can come off as cynical exchanges of credibility for exposure, with little of substance surviving these arrangements. But there are honourable exceptions, of course. And the art activities of Miuccia Prada - a committed and innovative collector and patron - count among them. In the Fondazione Prada, established in 1993 and headed by curator Germano Celant, she is developing one of the most interesting of private art institutes anywhere.

Its latest show, 'The Small Utopia. Ars Multiplicata', tackles the issue of art in the age of mechanical reproduction and how artists have used multiplication of various sorts. It contains over 600 items, produced between 1900 and 1975, and includes design, ceramics, glassware, textiles, film, magazines, books and sound recordings.

Unsurprisingly the father of conceptual art Marcel Duchamp is well represented here by over twenty works, including three editions of his seminal Boîte-en-valise of 1941, a brilliant piece in which he miniaturised his key works, including his infamous Fountain, and packaged them in a utilitarian leather case. Unpacked and assembled, it is a three-dimensional miniature retrospective, including all the artist's high points.

It is a prescient piece that perhaps reflects the truth of the 21st century: if the artists are not on the move, their works certainly are. With its reproductions and near self parody, Duchamp also set the scene for the 21st-century artist, demonstrating that one should never be too serious about one's work.

Andy Warhol, Duchamp's natural successor in terms of the popularising of contemporary art, is also well represented here, with cabinets of his now familiar Brillo boxes. Alongside are the far more serious but still inherently serial paintings of Josef Albers.  

The show is the Prada Foundation's second in the Ca' Corner della Regina, an enormous 18th-century palazzo it began leasing in 2011, opening during the 54th Venice Biennale with a stunning exhibition of Miuccia Prada's own collection. (As part of the deal, the foundation will gradually restore the palace, which was previously in parlous condition, while a permanent home, designed by Rem Koolhaas, is built in Prada's hometown of Milan). And there is vitrine after vitrine of books and objects fitting seamlessly into the overwhelming architecture of the palazzo.

In Duchamp's Boîte-en-valise, one finds the mustachioed Mona Lisa L.H.O.O.Q., a rectified readymade created from a cheap print. The title is a lascivious pun (understood when the letters are pronounced rapidly in French to mean 'she's got a hot ass'). Somehow this sharp-eyed irreverence seems to encapsulate Miuccia Prada's own vision.