The rules of celebrity engagement are rapidly changing.

The rise of social media has created a new generation of influencers who are competing with traditional celebrities. This trend was impossible to ignore over the past year when social media talent won some impressive brand deals.

A new report from Celebrity Intelligence in association with Econsultancy, “The Future of Celebrity Marketing,” attests to this and also finds agencies and brands in flux, debating, among other things, what exactly constitutes a celebrity.

The survey’s findings show that 74 percent of advertising agencies and 69 percent of companies queried, work with celebrities. While traditional celebrities such as film actors are still most relevant, social media talent is on the rise.

Advertising agencies are choosing to engage celebrities on a campaign-specific basis rather than a yearlong contract. This is true of 40 percent of the agencies questioned and 22 percent of companies queried. The social talent is being used for one-off promotions such as a tweet or Instagram post. About one-third of the agencies polled said they’re investing $15,000 to $75,000 on one-off campaigns.

“Social media influencers bring a lot of brand reach,” said Priyanka Dayal, content marketing manager of The Profile Group, Centaur Media plc. “They have engaged audiences. Social media stars make quick promotions and one-offs more accessible for brands. Having a face for [an entire ad] campaign is expensive.”

The impact of traditional media isn’t what it used to be. Network television’s ratings are eroding and many magazines have moved to the Internet. Generation Z, or those now 18 and under — which the report calls “the consumers of tomorrow” — watch their favorite brands on YouTube and view posts on social media. Meanwhile, Millennials, according to the report, spend about 18 hours a day taking in content.

“The change in media consumption is having a phenomenal impact on the celebrity world as we know it,” the report said. “Social stars enjoy a very different relationship with their audience and following, being more readily accessible than traditional celebrities. It’s not unusual for social talent to have online follower numbers that outstrip those of traditional TV or movie stars.”

Over the past few years, social stars such as Zoella and Chiara Ferragni have made the leap from YouTube to mainstream TV. Michelle Phan, who started her YouTube beauty channel in 2006, has more than 7.7 million subscribers, a makeup line, book and lifestyle network, Icon. Her video in which she transforms herself into Barbie has 64 million views.

While traditional celebrities still hold sway for brands that believe film and TV stars should be aspirational and not too accessible to the public, social talent has a much flatter playing field since audiences perceive stars as friends.

The survey found that 56 percent of company and 49 percent of agency respondents are undertaking in-depth research themselves to ensure the celebrities they work with reflect the core brand values of their campaign.

British retailer John Lewis recently named vlogger Jim Chapman, with 2 million Instagram followers and 2.5 million YouTube subscribers, as its inaugural men’s wear style curator. Presumably, Chapman was hired to attract younger consumers.

Burberry has used traditional models and celebrities in its campaigns, but unveiled the names of its brand ambassadors in a nontraditional way, via Instagram.

“It’s not either-or,” Dayal added. “They’re not taking away from each other. Fifty percent of agencies said their budgets will increase in the 12 months.”