Chuck Close calls them the mascots of the art world. Christo and Jeanne-Claude once offered them a drawing in exchange for taking care of their cat, Gladys, for a summer. The passion for minimalist and conceptual art that aging Manhattan collectors Herb and Dorothy Vogel have shared for nearly a half-century is sweet—if obsessive enough for a 12-step program—and has yielded one of the world’s major contemporary collections on a modest income. How did a retired postal clerk and librarian manage to accumulate thousands of important works (Picasso, Pollack, Schnabel), particularly when one of their buyers’ rules of thumb is that everything must fit in their rent-controlled one-bedroom apartment? Former journalist Megumi Sasaki’s warmhearted celebration of these adorable do-gooders—shot as the Vogels negotiated with the National Gallery of Art to take their collection for free (as one artist notes, asking the couple to sell even a single piece is like asking him to cut off a square yard from his painting)—cements their significance to the art world and introduces them to the rest of us. With no curatorial training beyond an instinctual “We like what we like,” watching the Vogels mull over art that they don’t need to understand only makes their delight more infectious.