As the digital media and advertising industries come to grips with the rise of ad blocking, so is one of the industry's more prominent organizing bodies.

A month before Apple revealed in June that later this year it would enable ad blocking on its mobile Safari browser, the Interactive Advertising Bureau broached the topic during its board meetings in May.

"We started taking a look at the remainder of 2015, and the ad-blocking conversation got ratcheted up based on what we were hearing from publishers and their data and the rise of [ad-blocking] incident rates they were seeing," said Scott Cunningham, a senior VP at the IAB and general manager of the trade organization's Technology Lab.

Since those discussions in May, ad-blocking has only grown as a practice among consumers and a concern for publishers and advertisers. In August Adobe and anti-ad-blocking firm PageFair reported that 198 million people around the world use ad blockers, which will cost publishers an estimated $21.8 billion in revenue this year. Both figures are likely to grow later this fall when Apple is expected to roll out a new version of its operating system for iPhones and iPads that will allow people navigating the web on its mobile Safari browser to block ads on publishers' sites.

"It's become a very important issue, and I think the IAB is doing a good job of trying to get ahead of it, although I don't know anybody that's really ahead of it," said WPP Digital President and Xaxis Chairman David Moore, who also serves as chairman of the IAB Tech Lab's board of directors. "It had to get big enough to be an important issue, and I think we've reached that inflection point."

To catch up with the growing issue, the IAB hosted a member leadership summit on July 9 at the IAB Ad Lab in New York City that convened the IAB and IAB Tech Lab boards as well as a number of sales and technology executives to discuss ad blocking. "It was more of an educational [meeting] to get the options on the table," Mr. Cunningham said.

Some of the options put on the table were a lot stronger than some of the more Pollyanna-ish calls for better ads or publisher appeals asking people to turn off their ad blockers as ways to fight ad blockers.

"I advocated for the top 100 websites to, beginning on the same day, not let anybody with ad blockers turned on [to view their content]," said Mr. Moore. He said that the other IAB members in attendance considered it "a good idea but the possibility of pulling it off slim."

That might not even be the most drastic option the IAB and its members are considering. The possibility of suing the ad-blocking companies is being explored.

The ad blockers "are interfering with websites' ability to display all the pixels that are part of that website, arguably there's some sort of law that prohibits that," Mr. Moore said. "I'm not by any means a lawyer, but there is work being done to explore whether in fact that may be the case."

"The IAB has a number of different outside counsels, and they're all counsels engaged by different companies [that are members of the IAB]. We're keeping a good temperature gauge around finding out what could be done," said Mr. Cunningham, who added that the organization is "far away" from a conclusion on whether legal action is a legitimate option. To buttress the point, Mr. Moore said that, "to say the IAB is going to mount a legal challenge at this time is not true because there's not been enough work done to assess whether that's a viable option."

Blocking content from people using ad blockers or suing the ad-blocking companies appear to be the nuclear options, but they are far from the only options being explored. The IAB Tech Lab has also organized separate working groups tasked with tackling different sides of the issue. One of these groups is determining how to improve the technology used to display ads so that ads will no longer be responsible for slower page-load times, which is one of the top reasons people install ad blockers. Another group is researching information about the type of people that use ad blockers to determine how tolerant they are of seeing ads in exchange for free content, which may be another way of asking "how will people respond if content is no longer free?"

Additionally, the IAB has adopted HTML5 as the new standard for display ads, replacing Adobe's Flash that causes pages to take longer to load and carries security vulnerabilities that have exposed people to hacking attacks.

And on Aug. 26, the IAB Tech Lab held another informational meeting that brought together four CEOs of companies that fight ad blockers -- PageFair, Secret Media, Sourcepoint and Yavli -- to school the IAB's domestic and international members on the technological ways to fight ad blocking.

"I think the most important takeaway [from that meeting] is that the ad-blocking firms themselves all reference very similar centralized lists of code to block," Mr. Cunningham said. That means that publishers may not have to fight a war on multiple fronts against each of the individual ad blockers, but could instead identify a way to combat them simultaneously.

"At this stage of the game, it's going to be up to the IAB to sort out what the most viable option is and get back to the membership for their input," Mr. Moore said. "Once that occurs, I think you'll see a strategy emerge before the end of the year."