The audiobooks story of the year in 2016 was—again—the continued strong sales growth of the digital audio market, and many audio publishers expect to see more gains in 2017.

Troy Juliar, chief content officer for Recorded Books, pointed to a convergence of consumer, technological, and demographic trends as a likely reason sales of digital audio will continue to grow this year. He stressed that listening to audio is becoming easier thanks to an increasing number of digital outlets for audiobooks in the U.S. and globally, as well as a proliferation of “smart speakers” and other integrated home systems from Google, Amazon, and others.

But, though listening at home is on the rise, the car remains the dominant, preferred place where people consume audiobooks. Michele Cobb, executive director of the Audio Publishers Association, is among those who say that is a big reason the CD format is still important, even as sales of digital increase rapidly. “Cars last a long time,” she noted. “I rent cars all the time, and they all have CD players.” In addition, Cobb said that technological advances have made producing small runs of CDs cost-effective, keeping the physical product viable.

As sales of audiobooks continue to rise, the industry is also maturing and gaining more attention from consumers. Juliar sees this as a gateway to new opportunities for audiobook companies, including finding ways to differentiate themselves from each other, experimenting with pricing, and pursuing international growth. “In some ways, the audiobook business is becoming less and less rooted in and connected to the overall book business; it is almost a separate thing affected and driven by different trends, and engaging people outside of traditional book channels,” he said.

At HarperAudio, v-p and audiobook publisher Ana Maria Allessi noted a similar trend. “I’m now seeing examples of ‘outlier’ titles where digital audio sales are strong compared to the e-book and print sales,” she said. “That used to be here and there, but it is happening consistently now. This gets us right in the middle of the conversation with authors and their titles. It’s a subtle but important distinction that has emerged over the last 12–18 months.”

This shift has also prompted Allessi to consider the timing of publication and to wonder if simultaneous audio and print publication matters as much as it once did. “We have always been beggars with the print side,” she said. “Now they come to us to ask what’s new and what we can do.”

According to Juliar, there will never be a complete separation of audio from the traditional print book world, “but if you look at the audiobook business purely through the lens of the traditional book business, you miss a lot of what is going on in this dynamic world.”

Authors have noticed this new exposure for audio and want to be a part of it. “They articulate their support for audio now,” Allessi said; she sees authors who are more agreeable to going the extra mile to get the word about audiobooks out. “The main job for all of us in publishing is to attract additional readers and listeners for our authors. The success of audio makes everyone very happy.”

Innovation is also in the forefront for audio publishers as they work to build awareness and expand the format. Many publishers are trying multivoiced recordings, short-form content, bonus audio-only material added to audiobooks, adaptations of such print formats as graphic novels, and more original content created for audio. HarperAudio has experimented with releases in the vinyl format, and Allessi mentioned “being creative with our marketing” on social media and elsewhere as a way to keep things fresh.

And it appears to be working. “Gwyneth Paltrow’s site Goop recently did an audio roundup, and we are getting more press coverage,” Allessi said. “We have broken through into the everyday.”

To meet the growing demand, title output will rise again in 2017. “We are still doing more titles because there are more people who are listening,” Cobb said. “All the publishers I’ve spoken with recently say they are doubling output again this year.” But the production volume is not without strategy, especially for smaller companies. “If you can’t do 800 titles, the 20 you do must be very much in [y]our audience’s sphere,” Cobb said.

At Penguin Random House Audio, senior v-p and publisher Amanda D’Acierno noted, “We’re on track to record more than 1,100 titles in 2017, up from nearly 900 in 2016.” In the year ahead, she said she’d like to see the format continue to expand, “particularly in children’s and young adult audiobooks,” citing the benefits of the format for building young listeners’ vocabularies and providing entertainment.

“Family listening is a memorable shared experience—there’s no comparison to a long road trip with Jim Dale narrating Harry Potter,” D’Acierno said. She is among the many publishers who believe that, despite several boom years in a row, there’s still plenty of room for industry growth. “While more listeners than ever are buying and using audiobooks, overall they are still a small piece of the overall book marketplace,” she added. “We still have millions of readers to reach with the message that audiobooks help you read anytime, anywhere.”