Paul Kasmin, a prominent British-born New York art dealer, has died at 60 after a long illness.

After operating a gallery in SoHo, he became a pioneering dealer in the Chelsea neighborhood, showing the work of great classical modernists, such as Brancusi and Motherwell, as well as introducing to America the playful work of the French duo Les Lalanne, who made sculptures of hippopotami, monkeys and sheep.

Kasmin was also an important patron of architecture, with four spaces in Chelsea, all designed by studioMDA, whose principal is Markus Doschantsch. The gallerist called the architect’s approach one “expressly crafted to show art at its best.”

Three of the four buildings studioMDA worked on for Kasmin were renovations of existing old buildings; the fourth and most recent was a ground-up structure right next to the High Line. The designs, each for a different scale of artwork, are highly rational with subtle distinctive details, like the linear black metal sashes for the entrance doors and windows. The final building, on West 27th Street, is the most unusual: it has an entrance framed by a deep surround of textured concrete; interior skylights set into a concrete grid (think Louis Kahn), and is topped by a green roof on which sculpture is displayed—a lovely public amenity visible from the High Line.