1. "We can't handle a crowd."

American museums will greet some 850 million visitors this year; that's more than the turnout for major-league sporting events and theme parks combined, according to the American Association of Museums. Among the major institutions, the Smithsonian's National Museum of Natural History brought in 7.1 million visitors in 2007, up nearly 27 percent since 2005, while the Museum of Modern Art in New York saw 2.2 million visitors in 2007, a 26 percent increase from 2005. But big crowds can lead to big problems.

Bruce Altshuler, director of New York University's program in museum studies, says it's becoming more difficult to find that quiet, contemplative experience people associate with a museum trip. "Many museums are too crowded to provide a certain kind of aesthetic experience," he says. At special exhibitions in particular, it's often so packed that it's hard to see what's on display, leading frustrated visitors to skip parts of the exhibit. Large crowds also lead to safety and security issues. Museums are especially concerned about having to evacuate visitors quickly in the event of an emergency, says Steve Keller, who runs a Florida-based security firm that specializes in museums.

2. "When we say our admission fee is optional, we don't mean it."

Only 35 percent of museums are free. Most ask for a "suggested donation," while a small percentage, like the Museum of Modern Art, have a set mandatory admission ($20 for adults at MoMA). But good luck telling the difference. Museums are making it increasingly difficult for visitors to decipher whether an admission fee is optional. At New York's Metropolitan Museum of Art, where a donation is suggested, a sign seems to imply there's an admission fee: "Free Admission if You Become a Member Today!" (A Met spokesperson says the sign causes no confusion for visitors.) "What museums are saying is, 'We want you to pay,'" says Stephanie Weaver, a museum consultant. "But they don't want to turn you away if you don't."

So what's the etiquette for entry? With government funding slipping, now's a good time to pay the full suggested donation. If money is tight, check to see if the museum offers reduced admission or free entry on certain days. Balboa Park's museums in San Diego take turns offering free admission on Tuesdays, and New York's MoMA is free on Fridays as long as you arrive after 4 p.m.

3. "We sometimes display stolen goods."

Museums rank just behind libraries as a trusted source of information, according to a recent survey by the University of North Carolina and the Institute of Museum and Library Services. But some museums are grappling with a credibility issue: the true ownership of their art. Thousands of artworks seized by the Nazis have ended up in American museums. "Sometimes museums will wonder, 'Is this stolen art from the Nazis?' But they'll never come out and say that," says Franklin Feldman, head of the law advisory council for the International Foundation for Art Research.

David Gill, an archaeologist at Swansea University in Wales, says many antiquities that can't be traced are presumed stolen. Countries like Italy, Greece and Egypt are asking museums to return artifacts if their ownership history can't be tracked prior to 1970. Gill says that in the pastyear, about 100 objects were sent back to Italy from museums in the U.S. Sharon Flescher, executive director of International Foundation for Art Research, says museums are "working hard to research their collections to find relevant gaps in the history of ownership."

4. "High culture sure ain't what it used to be."

For years museums have been rolling out special exhibits designed to draw large crowds and revenue. But today's blockbusters sometimes take hype to a new level. A recent traveling Star Wars exhibit showcased set props from all six films, and Giorgio Armani sponsored a show at the Met called "Superheroes: Fashion and Fantasy." Tickets can go for $30 or more, and big PR firms and corporate sponsors are joining the party. Companies like Premier Exhibitions, designer of traveling show "Bodies," are partnering with Ticketmaster to sell tickets. (Hello, surcharge!) Museums are even tapping into online sites like YouTube and Facebook to spread the word to younger audiences.

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High-profile exhibits help attract a broader array of visitors, but these blockbusters aren't always smash hits with the art community. Indeed, some people think the museums are simply selling out to popular culture. "Blockbusters respond so heavily to theperception of what people want to see that they inhibit a museum from exploring other topics," says Elizabeth Rodini, associate director of the Program in Museums and Society at Johns Hopkins University.

5. "Even you are on exhibit here."

Ever have the feeling you're being watched as you stare admiringly at a piece of art? You may be right. Market research and visitor studies are thriving in museums, with staffers noting things like how much time you spend in a given room. At the Exploratorium in San Francisco, a science and art museum, a team of staff "evaluators" follow visitors around and indicate on a map where they stop, what they observe and how they react. Other researchers might categorize you by personality type "experience seekers" are just there for a good time, while "spiritual pilgrims" seek refuge from the daily grind, according to Weaver, the museum consultant.

Why all this Big Brother-style observation? In part it's to make museums more consumer-friendly. So if you think the new DNA Discovery Center at the Field Museum in Chicago is a bit elementary, you can thank your peers. Through visitor surveys, exhibit evaluators discovered that few people really understood DNA or genetics. So the museum decided to bring the difficulty level of its exhibit down a couple of notches. "We like to make sure that we're not just speaking to ourselves," says Todd Tubutis, project director for the exhibition.

6. "It's all about the gift shop."

Museums might not have enough space to exhibit all their holdings, but they usually find room for a gift shop or two. Indeed, gift shops are more prevalent than ever especially those conveniently located at the end of special exhibitions. That rubs some people the wrong way. "You come out of an experience and are thrown into a commercial space," says Rodini. She'd rather see the gift shop separate from the exhibition so that "the experience of the galleries isn't cheapened."

The problem is, museums are banking on gift shops as a revenue stream, with stores bringing in anywhere from $35,000 a year for a small museum to several million a year for a major institution, according to the Museum Store Association. The Phoenix Art Museum sold French bath salts and glassware to visitors leaving its recent exhibit of French impressionist paintings. Others plaster art reproductions on everything from coffee mugs to T-shirts. "There's too much junk," says Kathy Borrus, co-owner of Retail Details, a Washington, D.C.-based firm that provides spaceand merchandising advice to museums."It's gone too far with items that are only marginally related."

7. "Our priceless treasures are languishing in storage."

Only about 5 percent of a museum's possessions are normally on display, with the remaining objects stashed away in storage. The Museum of Science and Industry in Chicago, for example, has more than 34,000 artifacts out of the public view. Kathleen McCarthy, director of collections, says the museum likes to have a wide range of artifacts to pull from to create new exhibits. And even though the museum says it has more exhibit space than any other science museum in the Western Hemisphere, it can simply run out of room: Many artifacts on permanent display "are quite large," says McCarthy.

There's a problem with keeping so much stuff under wraps. According to the Institute of Museum and Library Services, 65 percent of collection institutions have experienced damage due to improper storage. One solution would be more display space, of course, but that's not always possible. Paula Johnson, principal of Paragon Research Associates, a museum-consulting firm in Seattle, says some museums have a hard enough time making sure the roof doesn't leak "so having a bigger roof would not solve the problem for them."

8. "Companies aren't the only ones going private."

Private collectors are horning in on the global art market. Some decorate their homes with masterworks, while others build their own museums to showcase their treasures to the public. In Miami, real estate investors Don and Mera Rubell opened the Rubell Family Collection in1996, stocking it with the works of contemporary artists. Don Fisher, founder of the clothing retailer Gap, plans to open a contemporary-art museum in San Francisco by 2011, andAlice Walton, daughter of the late Wal-Mart founder Sam Walton, is financing the Crystal Bridges Museum of American Art, to open in 2010 near Wal-Mart headquarters in Arkansas.

Why the move toward privately held museums? Many are wary of donating their collections to public museums for fear the art won't get the treatment it deserves or will end up in storage. Los Angeles real estate developer and philanthropistEli Broad recently donated a $56 million building to the Los Angeles County Museum of Art but didn't commit to leaving his 2,000-piece contemporary-art collection to the museum. A spokesperson for Broad says the museum can borrow works of art as long as it's willing to keep them on display.

9. "You think our building is ugly; we say it's one of a kind."

Why is it that museums are often housed in such strange-looking buildings? High on culture and those who produce it, museums often hire "starchitects" to design their buildings or create a unique addition only to have them take their vision someplace few people can or want to follow. Sometimes, these new creations can get in the way of displaying the art. "Unfortunately, there's a tendency for the architect to make the experienceabout him rather than about the institution," says Art Wolf, a museum consultant in Las Vegas.

Critics had a field day with the Seattle Center's $240 million Experience Music Project. One compared architect Frank Gehry's curvaceous sheet-metal design to "a smashed electric guitar." Others weren't as polite. A critic for The New York Times wrote that the building resembled "something that crawled out of the sea, rolled over and died." Others described it as a "blob" and, more bluntly, one of the world's ugliest buildings. Museum CEO Josi Callan says that the building iscontroversial, but Gehry created "aunique piece of sculpture that is one of the most recognized pieces of architecture in the world today."

10. "Our collection's weirder than their collection."

The emergence of blockbuster exhibits in the late '70s started to blur the lines between museums and merchandising. But some are pushing the limits. Take the Jell-O Gallery, in Le Roy, N.Y., a museum for everything gelatin. Or the Mustard Museum, in Mount Horeb, Wis. "There's basically a museum for everything imaginable," says American Association of Museums President Ford Bell. At the SPAM Museum, in Austin, Minn., visitors can see how canned pork is made and check out exhibits like the SPAM Wall, displaying 3,390 cans of SPAM.

Not all bizarre museums are brand enhancements. In Philadelphia, the M tter Museum's collection of medical oddities draws doctors and medical students, along with the curious public. How to sort the wheat from the chaff? Do your research before visiting, and keep your expectations in line. Cynthia Robinson, director of the museum studies program at Tufts University, says museums that promote specific brands or are run by individuals don't always have the standards of a professional museum. "But 'museum' is a free word, and lots of organizations take it on."

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