A photograph is taken: camera up, frame the shot, click, and you own the moment. Or there’s the digital pilfering way: click, save, and it’s yours now. And his. And hers. This troubles Yunghi Kim, a photojournalist who got her first real job at the Quincy Patriot Ledger, in Massachusetts, around thirty years ago, taking pictures of parades and nursing homes. She has since travelled to Somalia, Rwanda, Kosovo, Iraq, and the Gowanus Canal, working during the eras of black and white, color, slides, and digital. Now, at fifty-two, she finds herself in the age of citizen Instagrammers, in which phones carry an endless roll of virtual film, and there are so many photos that we think we’re entitled to have them for free.

One rainy morning, in a coffee shop near her home, in Park Slope, Kim looked through the window at a street lined with parked cars. Bad light. She claimed that most of the images on the Internet are stolen. “Professional photographers see it as theft,” she said. “Photographs are our work, and our product. So it’s like this: There’s a lot of images on the Internet, right? Just like I see a lot of cars on the street. Am I going to go and steal one of those cars and drive it? Just because I see it, it’s mine?” She raised her eyebrows. “I’m going to get in trouble, right? I’m going to get arrested. I’m going to go to court. That’s why you have laws. Same thing with images on the Internet: just because you see it doesn’t mean you can take it.”

The opening screen of Kim’s Web site has a warning to visitors: “ALL IMAGES COPYRIGHT PROTECTED AND REGISTERED … IT’S UNLAWFUL TO REPOST, COPY OR PUBLISH IMAGES FROM THIS WEBSITE.” After a few seconds, the message fades away and a slide show of her pictures begins: children in exotic lands, a closeup of an old woman, a body sprawled lifeless in a refugee camp. Kim also has a blog called One Image at a Time, in which she posts a single, dramatic photo from years ago, culled as part of the ongoing task of digitizing her archives. Sifting through the old stuff, she returns in her memory to the instant the camera snapped—often surrounded by chaos and followed by a complicated procedure to render the image for print on the glossy page.

Color negatives went to the one-hour-photo shop—yes, she found one in Kosovo, in 1999, in the wake of the bombings and the death squads, and the mass expulsion of Serbian minorities during the reign of Slobodan Milosevic. She photographed refugees in black and white. “But the problem with black-and-white shooting in the field is that you couldn’t process it,” she explained. One-hour operations couldn’t do black and white. She had pictures of a boy standing in a field, his hands wrapped around his neck, children leaning on barbed wire, officers beating back the crowds. “So you’d have to ship the film,” she said. “You’d ship it in a cargo, or sometimes you’d give it to a person going on a plane.” She hoped the envelope would make it to the lab in New York. “Listen, life was hard back then as a photographer.”

The difficulty then was sending images from one place to another; the difficulty now arises from the ease of it. Not long ago, Kim did a reverse Google image search (put an image file, or a link to one, into the query box, and more like it pop up) for her pictures. She discovered that her Kosovo shots had gone viral. The boy in the field had gotten away—and with him what might have been fourteen thousand dollars. “There were, like, fourteen pages of it,” she said. “They were all on Italian sites. So this is the thing—I had to figure out, Oh, my God, what happened?” Panic set in. She looked into copyright law, and filed what are known as D.M.C.A. notices. The 1998 Digital Millennium Copyright Act allows photographers to demand the removal of their work from sites that unlawfully nabbed it. “It was just out of necessity that I was forced to protect my work,” she said. “And it was just out of necessity that I had to become an expert on copyright law. You can’t control all of it, but you can do as much as you can.” There’s software that can help photographers keep tabs, and services like ImageRights International, whose tagline is “It’s your image. You shot it. You created it. Now get paid for it.” Tracing infringements (and unwanted use in propaganda) is a part of any photographer’s job these days. “Professional photographers don’t talk about this publicly,” Kim said. “But they all do it.”

Last year, Andrew Paul Leonard, who uses a scanning electron microscope to photograph tiny subjects (think microbes and microglia) got $1.6 million in damages after a direct-sales company called Stemtech Health Services took his images. Several weeks later, a decision came down for Daniel Morel, a freelance photojournalist; Getty and Agence France-Presse used photos that Morel had shot in the aftermath of the earthquake in Haiti in 2010, and then posted to Twitter. The legal battle had dragged on—A.F.P. filed first, seeking a declaration that it didn’t infringe on Morel’s copyrights, then Morel made counterclaims—and the ruling was one of the first to establish rules for using images pulled from social media. “This was a landmark trial,” Kim explained. “The whole industry has been watching this for the past few years.” Morel was awarded $1.2 million.

Kim doesn’t get that much. Settlements are complicated. “Going through a lawsuit is incredibly crazy,” she said of Morel. “But he did go through it, and he said somebody had to stick up for the photographers. That case is not about the money, but it helps all of us.”

Some of Kim’s photos have been illegally posted in the United States, others in Europe or China; each country has its own legal system to contend with. “Either I invoice or I have to talk to lawyers,” she said. “It depends. Each situation is different.” She’ll also herald the call: “Photographers, just make some money. Somebody stole something that’s yours.” When a colleague wants to reach Google, Facebook, Twitter, or other major platforms, there’s often an online form or an e-mail address listed for D.M.C.A. notices; but, for some sites, finding the right person to ask is the hardest part. Kim began spreading the word, directing people to the appropriate contacts for take-down requests, and recommending watermarks to avoid thievery. Concentrate on Europe, she advised, where legal fees tend to be less expensive. In a message to photographers, she wrote, “I figure if I’m successful 75 percent of the time I’m still ahead of the game. Also, to limit my exposure, I only go after one offender at a time and settle that case before moving on to the next.” She added, “Remember, infringers don’t set the price of your work. You do! My settlements range from 1,000 to 3,000 euros plus legal fees for a single unlicensed image used for editorial purposes.” Kim told me that, in general, “For me, it’s financially worth pursuing.”

All of this takes time, but Kim doesn’t feel the pull to document conflict zones anymore. Her current project is a book of images from her archives. “The marketplace kind of stinks,” she said. “But, in terms of photography, I’ve had a very rich career.” She posts pictures online occasionally, but she’s wary of the Internet’s incessant bombardment of images. She doesn’t have an account on Instagram. “Images are now designed to drive traffic and clicks and followers,” she said. “I don’t really care about that.”