Nyhan will oversee planning, buying and other duties associated with the account, which includes well-known beverage brands such as Dr. Pepper, 7 Up and Snapple.
Previously, she was a senior account director at Impact Marketing & Promotions, working with clients such as Apple and Virgin America Airlines.
Cohen said Nyhan "has a strong media, creative and marketing background." She worked with Cohen at ABC for over a decade, becoming vice president, advertising and marketing--a role that covered all off-air advertising for the network, including prime time. The launch campaign for "Lost" has been frequently lauded, while "Desperate Housewives" became a breakout hit almost from the start.
Cohen served as executive vice president, marketing, advertising and promotion at ABC.
Before ABC, Nyhan worked in promotions at Fox as the network was establishing itself, going from two to seven nights a week of programming. Her duties included helping launch programming ranging from "Beverly Hills 90210" to the NFL, when Fox picked it up in 1994.
Cadbury, which Initiative took over in January, is one of several new pieces of business the agency has won recently, including Hyundai.