Art collectors all share a passion for art, but how and what they collect depends first and foremost upon their own personal tastes and passions. In the early 1970s, for example, when Barbara Pine began collecting architectural drawings, many sophisticated Manhattan galleries were showing conceptual art. "The dealers would talk on and on about it," she recalls. "I found it troubling. I didn’t enjoy it."

Around that time, Pine says, "there was a shift in my thinking." A former student of architectural history, Pine also had worked at the Art Institute of Chicago in education. "I used to go to schools and try to get children to come to the museum. I kept pointing out the buildings, the parks." Reminded of these experiences, Pine decided to pay visits to the architects Richard Meier and Michael Graves. "Graves was doing murals for house extensions in Princeton. I thought the murals were really beautiful and decided to ask about his drawings. I began seeing architectural drawings as art"

Now, nearly 35 years later, Pine's passion for architecture has blossomed into one of the world's preeminent collections of architectural drawings, which also formed the basis of the recent exhibit "Wright to Gehry: Drawings from the Collection of Barbara Pine" at Sir John Soane's Museum in London.

Rosa de la Cruz, a veteran of Art & Antiques' annual 100 Top Collectors list, tells a comparable story: "I was born in Cuba. Now I live in Miami, where 55 percent of the population is of Hispanic origin. I began collecting by looking south. I went a lot to Brazil, to Mexico, to Colombia. The idea was to try to integrate artists from those areas into the international circle." For de la Cruz, focus meant collecting—and promoting—contemporary Latin Americans. She and her husband, Carlos, began with Ana Mendieta and José Bedia from Cuba, and Jac Leirner from Brazil in the late 1980s. In the early 1990s, they collected works by Felix Gonzales-Torres (Cuba), Gabriel Orozco (Mexico) and Ernesto Neto (Brazil). Now, during the annual Art Basel Miami Beach, the de la Cruz collection has become a revered destination, serving as a stage for contemporary art. "It's been important for me," says de la Cruz, "to share my art with other people, to open my house."

The message couldn't be clearer: Personal passions often take time to identify. When Pine first began collecting, she says, "I had some paintings from the 1950s—a Jim Dine, a Sam Francis. I was collecting modern art. I was also collecting works on paper." Likewise, recalls de la Cruz: "At first we were buying modern art, but then a friend said, 'You have such a passion. You should be collecting something happening today, not on the secondary market.'" Henry Buhl, whose vast photography collection was presented in the 2004 Guggenheim Museum exhibit "Speaking With Hands," collected haphazardly for several years before settling on the unifying subject of hands.

Identifying Your Unique Passion

Following are some tips on how to hone your collecting habits:

Focus on a historical movement or moment, like Pop Art, German Expressionism or 9/11. Or use your collection to champion a limited number of artists that you collect in depth. For example, Chicago collectors Dorothy and Alan Press collect Ed Ruscha and H.C. Westermann almost exclusively.

Explore a genre. Judith Brown, a former newspaper editor and publisher, collected limited-edition prints bearing images of newspapers.

Build a bridge between art and other disciplines. For example, "Matisse: The Fabric of Dreams," a recent show at New York’s Metropolitan Museum of Art, presented Matisse's paintings and drawings alongside the fabrics appearing in those works. And "On the Wall: Contemporary Wallpaper," co-curated by Judith Tannenbaum at the Rhode Island School of Design Museum in Providence, shows the importance of looking closely at what's already available in one's own collection. "RISD has a historic collection of wallpaper," says Tannenbaum, the museum's curator of contemporary art. "That's what makes this place unique. When I became aware of artists trained in contemporary painting and sculpture who were also making wallpaper, I found a way of connecting the two. Ultimately, it enabled us to grow the collection further, by accessioning some of those contemporary pieces."

Consider broader applications. Eventually de la Cruz achieved her goal of integrating Latin American artists into the international art circuit. For the past several years, she and her husband have been collecting more globally. Still she remains close to her Latin American roots. "Now we’re doing installations, which take a lot of space," she says. "Ernesto Neto did a site-specific work, a utopian space. It's made of soft materials, which is very Brazilian: latex, stockings and sand. You need to remove your shoes before you enter. It's very beautiful to walk in a soft space. It's very close to the feeling of a body. Or you could be inside a cloud."

Regardless of your approach, let your interests and passions guide you. "First look and decide what you really love and what interests you," Pine advises emerging collectors. "If it's just a casual interest, you'll never have the motivation to stick to it. If it's a real passion, you'll stay focused."

Dorothy Spears is a former curator of Leo Castelli's private collection at the Leo Castelli Gallery in New York and is a member of the Friends of Contemporary Drawing at the Museum of Modern Art.