Hershey Co. has launched a creative agency review as the candy giant looks to expand its roster of agencies beyond Arnold Worldwide and Havas Worldwide, both owned by the Havas holding company. The two shops will remain on the company's roster, but the marketer wants to get ideas from a broader range of agencies.

"We are just looking to add more [agencies] to the mix to help diversify the work," said company spokeswoman Anna Lingeris. The company, she said, wants to develop "better effectiveness and efficiencies over time."

Hershey has been with Arnold for more than eight years and with the Havas agency for three years. Havas had traditionally handled digital and Arnold was on TV, but Hershey increasingly looks at the shops as a "collaborative team" as digital and traditional media have converged, Ms. Lingeris said. "We are not replacing them. We are just looking to add selective agencies to create a … world-class team," she added.

The review will be handled internally, and Hershey has already notified agencies invited to the review, she said. Hershey was the nation's 63rd-largest advertiser in 2013, spending $668 million, according to the Ad Age DataCenter.